Field Manual Of Trees

Survival, Water, Medical Field Manuals

Military Manuals

Schaffner John H.

Document text

Irla Central librarp . 


PILANT (Jaipur State) 

Class No :- SSi U 

Book No > S / ^ /^ 


i 


Accession No 


dS'S'S'S I 










FIELD MANUAL 
of TREES 


Including Southern Canada and the 
Northern United States to Approxi- 
mately the Southern Boundary of Vir- 
ginia, Kentucky and Missouri, West- 
ward to the Limits of the Prairie 


FOURTH REVISED EDITION 


By 


JOHN H. SCHAFFNER 

Research Professor of Botany 
and formerly Head of the Department of Botany, 
Ohio State University 


R. G. ADAMS & COMPANY 
Columbus, Ohio 
1936 



<'o|Mriirht 1930 
lU 

John II. Srhaffner 



PREFACE 


This little manual represents a revision of the author’s 
former “Trees of Ohio and Surrounding Territory,” and at- 
tempts to carry out more definitely the idea of having a 
convenient guide by which it is possible to study our trees 
at any season of the year. The keys have been made very 
complete so that no difficulty should be encountered in iden- 
tification except in the case of closely related species. No 
elaborate technical descriptions have been given but a few 
brief notes are added in connection with each species, calling 
attention to economic, ecological, or other data of general 
interest. Characters given in the keys are usually not re- 
peated in the descriptions. A definite characterization is 
also given for each genus. This will be found to hold for 
all the species occurring in our region and in most cases 
for all the species of the genus. 

The nomenclature is in agreement with the International 
Rules of Botanical Nomenclature and a few changes in names 
from those used in previous editions will be found. Only 
three generic names are involved but a considerable number 
of specific names, some through the application of the 
rules and some from our more advanced knowledge of the 
subject. A rather conservative position has been taken in 
the treatment of species since many of the forms recently 
described are regarded as merely elementary varieties 
either Mendelian or ecological, A single English name is 
given for each species, and this has been selected with 
great care. Synonyms will be found in the index. 

Some of our common, cultivated, exotic trees have been 
included, since these form an integral part of the landscape, 
in many places more conspicuous than the native species. 

The study of trees may be made a pleasant and profitable 
pastime at any season of the year for all who have an inter- 
est in nature. When the tree has once been identified its 


(a) 



6 


Field Manual 


as it frequently happens when some of the cross walls are 
broken down in a vertical series of cells. The large cells in 
the wood, however, are called wood vessels. Just how the 
water is able to pass up to the tops of high trees is not fully 
understood. In early spring, as in the sugar maple, the water 
accumulates in the sap wood, since there are no leaves from 
which it can be thrown off above. 

The crown is a system of branches on which the leaves 
are developed and exposed to the light. In the leaves most 
of the food is manufactured which the tree uses for its 
growth and nourishment. This production of organic food 
is carried on through the agency of sunlight and chlorophyll, 
as the green coloring matter is called. Another important 
function of the leaves is the transpiration of the surplus 
water brought up from below. The water transpired by a 
large tree in a single day is often very great in amount. The 
leaves are also important breathing organs, although not ex- 
clusively so; for all the living cells in the entire plant carry 
on the process of respiration. 

The system of branching in the crown may be of various 
types. If the main trunk of a tree extends upward through 
the crown to the tip it is said to be excurrent, as in the larch 
and white pine. When the terminal bud has no preeminence 
over others and the main trunk is soon lost, the tree is 
round-topped or spreading and is said to be deliquescent, as 
in the apple. Excurrent trees are often spire-shaped like the 
Norway spruce; while deliquescent stems commonly give rise 
to dome-shaped crowns, as in the white elm. If the terminal 
bud withers or is self-pruned, as in the linden or elm, the 
branching is sympodial. If the leaves are opposite and the 
two lateral end buds develop, the terminal bud being self- 
pruned, the result is a sympodial dichotomy ,as in the blad- 
dernut. Trees in which the terminal buds are persistent and 
functional are said to have a monopodial system of branching. 

The trunk or any branch of a coniferous or dicotylous 
tree consists of four main parts, the pith, the wood, the 
cambium or growing layer, and the bark. The wood consists 
of a series of annual rings, since if normal growth takes 
place only a single ring is produced each year. Each ring 



Trees of the Northern United States 


7 


usually consists of two layers called early wood and late 
wood. During special seasons or if growth is checked at 
times during the growing period more than one ring may be 
produced, although this is never perfect and can usually be 
detected by careful examination. In most trees the inner part 
of the wood and the pith are dead and this is called the heart 
wood or duramen, while the outer wood is lighter in color 
with living cells next the cambium layer, and is called the 
sap-wood or alburnum. Sometimes there is a striking dif- 
ference in the color of the two parts. Strands of cells pass 
from the pith or annual rings through the wood to the bark. 
These are called medullary rays. The peculiar qualities of 
wood are due to the character of its cells which have their 
walls lignified or thickened by deposits of lignin and cellulose. 

The bark usually consists of two main layers called inner 
bark and outer bark. The inner bark is often in very thin 
layers and is hence called liber. The outer bark is very 
diverse in character. Usually it consists mainly of layers of 
cork cells which are very impervious to water. Since the 
outer bark usually does not increase in diameter as rapidly 
as the wood it is finally torn into strips and peels off on the 
outside. Trees have many interesting ways of developing and 
getting rid of their outer bark. 

More commonly the outer bark is developed as follows : 
In a young main stem or twig there is a tissue between the 
outer layer of cells or epidermis and the circle of vascular 
bundles which is called the cortex. While the stem is de- 
veloping and hardening, the outermost layer of cortical cells 
just below the epidermis is modified and begins to grow. 
This layer is the cork cambium or phellogen. The layer of 
tissue thus formed by the repeated divisions of the cells of 
the phellogen is called the periderm or cork. On the inner 
side of the phellogen another layer of tissue is produced 
which is called the phelloderm or secondary cortex. The 
phellogen may continue to produce periderm until the outer 
bark becomes very thick ; and finally new cork cambiums 
may develop farther in the cortex or even in the phloem of 
the inner bark. In some plants the cork cambium origi- 
nates from the epidermis and in some from the deeper layers 
of the cortex. 



8 


Field Manual 


Some trees have no special means of shedding their leaves 
while others shed them only after a year or more. Most of 
our indigenous species are “deciduous,” that is they cast their 
leaves at the end of each growing season by the formation 
of a cleavage plane or separation layer through the base of 
the petiole. Some also prepare for winter by developing 
elaborate winter buds. The function of the winter buds is 
mainly advantageous in checking evaporation from the deli- 
cate stem tips during the periods of freezing and thawing. 
Some trees have so-called naked buds, that is buds without any 
special scale leaves. 

Many of the smaller branches and twigs of a tree, espe- 
cially when growing in a dense forest, are continually dying 
off. But the tree rids itself of these dead branches by form- 
ing a collar of tissue from the cambium layer around the base 
of the dead branch, which finally covers over the wound 
when the dead member falls off. This process is known as 
natural pruning. By the formation of a similar callus other 
wounds are covered up. There is still a more remarkable 
process present in many trees by which surplus living branches 
are cut off in one way or another. Terminal and lateral buds 
are also commonly cut off. This process of abscission is 
known as self-pruning. The most common method is by the 
formation of a cleavage plane in a basal joint or in the 
annual nodes of growth. In some genera brittle zones are 
produced. The self-pruning process is very highly developed 
in the cottonwood, white oak, white elm, and silver maple. 

Trees grow in height only at the tips of the main stem 
or branches. Some trees are naturally shortlived ; others 
attain an enormous size and age, but from the very nature of 
their upright development their life must sooner or later come 
to an end. In some cases the individual organism may con- 
tinue by a new development from sprouts growing out of the 
stump or the roots. 

All of our native trees bear flowers and seeds. After ar- 
riving at a certain age depending on the spceies, the tips of 
some twigs or the axillary buds will develop flowers. In 
the more highly developed and typical flowers, as in the An- 
thophyta, four sets of organs are present: the caylx composed 
of sepals, the corolla composed of petals, the andrecium com- 



Trees of the Northern United States 


9 


posed of stamens, and the gynecium composed of carpels. The 
two essential sets of organs in the flower are the stamens and 
the carpels. These are the sporophylls and may both be in the 
same flower, when the flower is said to be bisporangiate or in 
separate flowers, when the flower is monosporangiate. If 
the staminate and carpellate flowers are on one individual 
the plant is monecious, if on two d^tinct individuals the 
plant is diecious. In this case the plants are spoken of as 
staminate trees and carpellate trees. The stamens produce 
microsporangia and the carpels megasporangia or ovules. In 
the Anthophyta the carpel usually has three parts called 
stigma, style and ovulary, the ovules being completely in- 
closed in the ovulary. Commonly all the carpels of the gyne- 
cium are grown together and in such cases a compound ovulary 
is produced with one or more cavities. 

In the gymnosperms, which include the Strobilophyta or 
our common evergreens, the flower is of a more primitive 
type and is usually called a strobilus or cone. The carpels 
are not closed around the seeds, hence there is no ovulary, 
but the seeds are exposed as the name gymnosperm implies. 
The frequently cultivated Ginkgo tree is the lowest type of 
tree growing out of doors in our region and has leaves that 
remind one of the leaflets of a maiden-hair fern. It is the 
only tree we have that is completely flowerless. The stamens 
and carpels are borne in rosettes with the foliage leaves on 
dwarf branches which continue to grow from year to year, 
often for a long time. This condition is therefore similar 
to what is present in the tree ferns, the plant having no 
determinate axes of any kind. 

Following a peculiar process known as the reduction divi- 
sion which takes place in the cells inside of the microspo- 
rangium, a considerable number of microspores are developed, 
four for each original cell. In nearly the same way, four 
megaspores, one of which survives, are usually produced in 
each ovule. The flowers are thus modified spore-bearing 
branches or shoots of determinate growth producing two 
kinds of reduction spores. The flowers are nonsexual organs 
and the tree itself is always a nonsexual plant called the 
sporophyte, although some of its parts may show secondary 
sexual characters and dimorphisms. It is nonsexual only in 



10 


Field Manual 


the sense that no gametes (eggs and sperms) are produced 
directly. The microspores germinate and develop into the 
pollen grains and the megaspores into the so-callcd embryo 
sacs, or minute, parasitic, male and female gametophytes re- 
spectively, which arc the real sexual generation. After pollina- 
tion has taken place, which is simply the transfer of the 
pollen to the ovules or to the stigmas, a tube grows from the 
pollen grain into the female gametophyte. The two sperm 
cells produced in the pollen grain or in the pollen tube pass 
down the tube and one unites with the egg cell of the female 
gametophyte. This union of sperm and egg is called fertiliza- 
tion. The resulting cell which is the oospore germinates and 
gives rise to an embryo inside of the ovule, the whole finally 
constituting the body called the seed. In the Anthophyta, en- 
dosperm is produced in the seed by the union of the second 
sperm with two cells from the female gametophyte. This 
embryo in the seed is the sporophyte and after sprouting de- 
velops into the tree. The seed is produced inside of or in 
connection with the modified carpels and other contiguous parts, 
the whole being called the fruit. The fruits of our trees are 
of many types usually with some means for seed distribution, 
so that the seed with its little embryonic tree inside may be 
carried away from the parent plant to some other and perhaps 
more favorable environment. Here, if conditions are proper, 
it sprouts and begins its life as an independent individual. The 
whole process of flower, seed, and fruit production is ex- 
ceedingly complex and requires close study and observation 
if one would know the more obscure activities going on during 
the life cycle of a tree. 



KEY TO THE GENERA OF TREES IN THE 
SUMMER CONDITION 


Based mainly on leaf and twig characters. The number 
following the generic name refers to the list number. 

1. Foliage leaves with expanded blades, netted-veined. 8. 

1. Foliage leaves needle-shaped, narrowly linear, subulate, 
or scale-like ; conifers. 2. 

1. Foliage leaves fan-shaped with dichotomous venation, a 

number on thick, wart-like, persistent dwarf branches. 

Ginkgo. (1). 

2. With typical dwarf branches, persistent for more than 

one year. 3. 

2. With feather-like dwarf branches, deciduous each year, 
the linear leaves spreading into 2 ranks, or very short. 

Taxodium. (2). 

2. Without dwarf branches. 4. 

3. Dwarf branches small, self-pruned, with 2-5 foliage 

leaves. Pinus. (7). 

3. Dwarf branches thick, wart-like, persistent, with nu- 

merous deciduous leaves. Larix. (6). 

4, Leaf buds scaly ; leaves scattered. 5. 

4. Leaf buds not scaly, naked ; leaves opposite or whorled. 7. 

5. Leaf scar on a sterigma, the twigs covered with scales 

representing the leaf bases. f3. 

5. Leaf scar on the bark; twigs without scales; leaves 

flat. Abies. (5). 

6. Leaves flat, those on the upper side of the twig much 

shorter than the lateral ones; trees. Tsuga. (4). 

6. Leaves more or less 4-sided, spreading in all direc- 

tions. Picea. (3). 

7. Foliage leaves small, scale-like, appressed, opposite, 

4-ranked, closely covering the twigs which are de- 
cidedly flattened and fan-like; leaves of two shapes, 
the dorsal and ventral broader and less acute than 
the lateral ones; scales of the carpellate cone 6-10, 
not peltate. Thuja. (8). 


( 11 ) 



12 


Field Manual 


7. Foliage leaves small, scale-like, appressed, opposite, 4- 
ranked, usually long decurrent, on somewhat flat- 
tened branches; scales of the carpellate cone 4-6, 
the two middle fertile, not peltate. 

Libocedrus. (9). 

7. Foilage leaves small, scale-like, appressed, opposite, 4- 
ranked, closely covering the slightly flattened twigs 
which are not very fan-like ; leaves nearly or quite 
similar; scales of the carpellate cone peltate. 

Chamaecyparis. (10). 

7. Foliage leaves of two types, scale-like and subulate, 

opposite or in threes; the scale-like leaves 4- 
ranked, appressed, causing the twigs to appear 
quadrangular, the subulate leaves spreading; one or 
both types of leaves on a plant; carpellate cone 
developing into a bluish-black, berry-like fruit. 

Juniperus. (11). 

8. Leaves alternate. 9. 

8. Leaves opposite or whorled. 74. 

9. Leaves simple. 10. 

9. Leaves compound. 62. 

10. Leaves pinnately veined or with a simple midrib, 11. 

10. Leaves palmately veined or at least with 2 or more promi- 

nent side ribs coming from, near the base of the blade. 
53. 

11. Leaves truncate or broadly emarginate; with complete 

stipular rings at the nodes. Liriodendron. (13). 

11. Leaves entire. 12. 

11. Leaves serrate, dentate, crenate, pinnatifid, or variously 

lobed. 26. 

12. With stipular rings at each leaf node; leaves large. 

Magnolia. (12). 

12. Not with stipular rings. 13. 

13. With thorns and milky sap. 14. 

13. Without thorns; sap not milky. 15. 

14. With thorns beside the axillary buds; leaves not taper- 

ing at the base, acute or even heart-shaped. 

Madura. (65). 



Trees of the Northern United States 


13 


14. With terminal thorns and some axillary thorns; leaves 

tapering to the base; narrow or slender>cuneate. 

Bumelia. (24). 

15. Leaves evergreen, coriaceous, some on wood of the pre- 

vious season. 1(>. 

15. No leaves on wood of the previous season, 17. 

IG. Leaves green on both sides, thick, coriaceous, oblong to 
oblanceolate, 5-10 in. long; winter buds very scaly. 

Rhododendron. (21) 

16. Leaves green on both sides, or glaucous beneath, 

coriaceous, 2-5 in. long; oval or oval-lanceolate, 
winter buds naked. Kalmia. (22). 

IG. Leaves bright green above, paler beneath, coriaceous, 4-5 
in. long, pointed at both ends; bark aromatic. 

Persea. (15). 

17. Pith with prominent diaphragms but solid; vascular bun- 

dles in base of petiole 3-7. 18. 

17. Pith not both diaphragmed and solid, but sometimes 

with lenticular cavities. 11). 

18. Leaves 2-ranked; bark with fetid odor; vascular bun- 

dles in base of petiole 5-7. Asimina. (14). 

18. Leaves not 2-ranked; vascular bundles in base of 

petiole 3. Nyssa. (79). 

19. T. eaves resin-dotted, waxy-dotted or punctate, oblong, 

lanceolate, spatulate, or oblanceolate, short-pointed, 
narrowed at the base. Myrica. (75). 

19. Leaves not dotted nor punctate. 20. 

20. Pith prominently 5-angled; leaves with deciduous 

stipules and with bristle tips. Quercus. (66). 

20. Pith cylindrical or nearly so; leaves not bristle-tipped. 21, 

21. Leaves with the upper 2 lateral veins more or less 

parallel with the midrib. Cornus. (80). 

21. Leaves pinnately veined to the tip. 22. 

22. Bundle scar central ; pith sometimes diaphragmed with 

lenticular cavities. 23. 

22. Bundle scars 2 or more; pith without lenticular cavi- 

ties. 24. 

23. Leaves truncate or short-pointed at the base, usually 

widest below the middle or somewhat oblong, 



14 


Field Manual 


glabrous when mature; fruit a large pulpy berry, 
very astringent when green. Diospyros. (25). 

23. Leaves pointed at the base, widest above the middle, 

lower surface pubescent; fruit a nut-like drupe. 

Symplocos. (26). 

24. With prominent deciduous stipules; bark not resinous. 

Cydonia. (38). 

24. Without stipules; bark resinous, aromatic. 

Cotinus. (56). 

-25-- 


25. Lateral veins from the midrib straight and parallel or 
nearly so; some or all lateral veins usually ending in 
the serrations, teeth or lobes. 26. 

25. Lateral veins not straight and parallel. 37. 

26. Leaves not 2-ranked. 27. 

26. Leaves of normal twigs quite regularly 2-ranked, that is 

with the third leaf over the first. 30. 

27. Pith 3-angled, buds stalked. Alnus. (72). 

27. Pith 5-angled, buds not stalked. 28. 

27, Pith cylindrical or nearly so. 29. 

28. Leaves or their lobes bristle-tipped, or if not bristle-tipped 

then the teeth or lobes not sharply acuminate; buds 
clustered at the tip of the twig; nut in a cup-like in- 
volucre of numerous scales. Quercus. (66). 

28. Leaves with sharply acuminate teeth; buds not clus- 

tered at the tip; nuts with a prickly or spiny invo- 
lucre. Castanea. (67). 

29. Usually with prominent and typical lateral thorns; 

carpels of the pome bony. Crataegus. (40). 

29. Without thorns but sometimes with thorn-like 
stunted branches; leaves irregularly dentate, ser- 
rate or crenate-dentate; sometimes lobed; pome 
fleshy without grit cells; carpels papery or leath- 
ery. Malus. (36). 

29. Without thorns; leaves serrate or se»*rate-dentate; 

pome berry-like, carpels not bony. 

Amclanchier. (39). 

30. Leaves decidedly inequilateral at the base. 31. 



Trees of the Northern United States ir> 

30. Leaves not inequilateral or only very slightly so. 32. 

31. Axillary buds prominently stalked; leaves repand- 

dentate. Heamamelis. (57). 

31. Buds sessile; leaves doubly serrate, bark not scaling 
off in plates. Ulmus. (62). 

31. Buds sessile; leaves serrate, bark scaling off in plates 

like in the Sycamore. Plancra. (61). 

32. Lateral veins ending in the large dentations or serrations 

which are always simple (a vein for each). 33. 

32. Leaves doubly serrate or sometimes simply serrate, the 

lateral veins ending in the main serrations or teeth 
but in the smaller ones, or the veins not ending in 
the serrations. 34. 

33. Leaves ovate or ovate-oblong, short acuminate ; teeth 

not with slender points; bark smooth, light gray. 

Fagus. (68). 

33. Leaves oblong-lanceolate, acuminate, with slender often 

inwardly curved points on the serrations ; bark rough. 

Castanca. (67). 

31. Lateral veins not ending in the serrations or teeth. 

Amelanchier. (39). 

34. Lateral veins ending in some of the serrations, teeth or 

lobes. 3t5. 

35. Bark smooth, the trunk and larger branches with 

fluted or projecting, muscle-like ridges; leaves 
acute or acuminate, sharply double serrate; nuts 
small, in a largc-bracted catkin. Carpinus. (69). 

35. Trunk and larger branches not with fluted or projecting 

ridges. 36. 

36. Bark of trunk and larger branches separating into 

papery or leathery sheets; trees or shrubs with 
glabrous, pubescent, or glandular warty twigs. 

Betula. (71). 

36. Bark of trunk scaly, fine furrowed; twigs glandular- 
bristly; carpellate catkin in fruit appearing like 
that of the hop. Ostrya. (70). 

36. Bark scaling off in plates like in the Sycamore; fruit 
coriaceous, nut-like. Plancra. (61). 



16 


Field Manual 


— 37 — 


37. Leaves 2-ranked. 38. 

37. Leaves not 2-ranked. 39. 

38. Bark of trunk and larger branches separating into papery 

or leathery sheets ; leaves doubly serrate, the lateral 
veins ending in the main serrations, teeth or lobes. 

Betula. (71). 

38. Bark not in papery or leathery sheets; leaves not 

doubly serrate, the lateral veins not ending directly 
in the serrations or teeth. Amelanchier. (39). 

39. Leaves not with spines. 40. 

39. Leaves evergreen, with spine-tipped lobes. 

Ilex. (48).. 

40. Pith not solid, diaphragmed, with lenticular cavities. 41. 

40. Pith solid but with prominent diaphragms; vascular 

bundles 3 in the base of the petiole. Nyssa. (79). 

40. Pith solid, without diaphragms. 42. 

41. Leaves oval or obovate, serrate or denticulate, ab- 

ruptly acuminate, wedge-shaped at the base, more 
or less stellate pubescent beneath; bark of twigs 
peeling off in slender shreds; fruit 4-winged. 

Halesia. (27). 

41. Leaves oblong or slightly obovate, acute or acuminate 

at both ends, crenate-serrate or repand, short petioled; 
twigs of the season and lower surface of leaves pubes- 
cent, not stellate; fruit a nut-like drupe. 

Symplocos. (26). 

42. Leaves with peltate scales, or resin-dotted, oblan- 

ceolate or wedge-lanceolate. Myrica. (75). 

42. Leaves not peltate scaly, nor resin-dotted. 43. 

43. Outer bud scales of winter buds more than 1. 44. 

43. Outer bud scale 1; twigs with brittle zones, hence 

easily detached and leaving peculiar self-pruning 
scars; terminal bud of ripe branches absent; bun- 
dle scars or vascular bundles in base of petiole. 3. 

Salix. (77). 

44. Pith decidedly 5-angled. 45. 

44. Pith cylindrical or nearly so. 46. 

45. Bundle scars 3; leaves with gland-tipped teeth, usu- 



Trees of the Northern United States 


17 


ally broad-based, usually with 2 prominent glands 
at the base of the blade. Populus. (76). 

45. Bundle scars several, scattered; leaves without 

glands; buds clustered at the tip of the twig. 

Quercus. (66). 

46. With stipules or stipular scars. 47. 

46. Without stipules or stipular scars; leaves sour, with 

prominent scattered hairs on the midrib beneath ; 
fruit a capsule. Oxydendrum. (23). 

47. With typical lateral thorns; fruit a drupe-like pome 

with bony ripe carpels. Crataegus. (40). 

47. Not with typical lateral thorns, but some may have thorn- 

like stunted branches. 48. 

48. Leaves with 1 or more disc-like, wart-like, or tooth-like 

glands on the petiole or at the base of the blade. 49. 

48. Leaves not with distinct glands on the top of the petiole 

nor at the base of the blade, but they may be glandular- 
hairy. 50. 

49, Twigs green, red, or red and green; nectar glands disc- 

like, usually 2-4 near the base at the edge of the blade; 
terminal bud present; fruit a velvety drupe. 

Amygdalus. (34). 

49. Glands various; twigs not red and green, some with 

cleavage planes in basal joints; terminal bud pres- 
ent or absent, fruit a smooth drupe. Prunus. (33). 

50. Axillary buds usually superposed; leaves lanceolate 

or oblong-lanceolate, tapering towards the short 
petiole; fruit a berry-like drupe. Ilex. (48). 

50. Axillary buds not superposed. 51. 

51. Leaves with gland-tipped serrations; terminal bud absent 

on ripe twigs or if present then the lateral veins promi- 
nent and’ nearly parallel and curving upward at the 
margin of the leaf; fruit, a berry-like drupe. 

Rhamnus. (46). 

51. Leaves not with gland-tipped serrations or if so then 

not as above; terminal bud present; fruit a pome. 52. 

52, Leaves sharply and regularly serrate, glabrous when 

mature, petioles long; pome with grit cells. 

Pyrus. (37). 



18 


Field Manual 


52. Leaves irregularly dentate or serrate, or more or less 

lobed; pome without grit cells.. Malus. (36). 

— 53 — 

53. Base of petiole covering the axillary bud; twigs with 

stipular rings. Platanus. (59). 

53. Axillary buds usually evident ; twigs without stipular 

rings. 54. 

54. Leaves on normal twigs 2-ranked. 55. 

54. Leaves not 2-ranked. 60. 

55. Leaves entire, round-heart-shaped., Cercis. (43). 

55. Leaves serrate, dentate, or lobed. 56, 

56. Pith usually in transverse plates; leaves ovate-lance- 

olate, inequilateral, taper-pointed. Celtis. (60). 

56. Pith solid, not diaphragmed. 57. 

57. With milky sap. 58. 

57. Without milky sap. 59. 

58. Twigs gray or brown, glabrous or nearly so; leaves 

pubescent or glabrous beneath. Morus. (63). 

58. Twigs grayish-green, downy; leaves tomentose beneath. 

Broussonetia. (64). 
59.. Leaves not inequilateral; vascular bundles in base of 
petiole 3. Betula. (71). 

59. Leaves inequilateral at the base; vascular bundles in 

base of petiole several, scattered. Tilia. (20). 

60. Leaves more or less star-shaped, with 3-7 long 

pointed serrate lobes, strongly aromatic when 
crushed; pith 5-angled. Liquidambar. (58). 

60. Leaves entire or three-lobed, bark spicy-aromatic; 
internodes very unequal. Sassafras. (16). 

60. Leaves crenate,* serrate, dentate, or lobed, not star-shaped 

and not spicy-aromatic. 61. 

61. Pith 5-angled; trees usually with resinous buds; 

leaves usually broad based. Populus. (76). 

61. Pith cylindrical or nearly so; usually with prominent 

typical thorns. Crataegus. (40). 

— 62 — 

62. Pith diaphragmed, with cavities; large trees with pin- 

nate leaves. Juglans. (74). 



Trees of the Northern Unitei> States 


19 


62. Pith not diaphragmed. 63. 

63. Leaves trifoliate, odd-pinnate or odd-bipinnate. 64. 

63. Leaves evenly pinnate or bipinnate; axillary buds super- 

posed. 73. 

64. Lobes or teeth at the base of the leaflets with promi- 

nent green glands beneath; leaves pinnate, very 
large with disagreeable odor. Ailanthus. (19). 

64. Lobes or teeth if present without green glands. 65. 

65. Leaflets glandular punctate ; pith not 5-angled ; small trees 

or shrubs. 66. 

65. Leaflets not punctate. 67. 

66. Leaves pinnate, with stipular spines. 

Zanthoxylum. (17). 

66. Leaves trifoliate, without stipular spines; bark with 

disagreeable odor; axillary buds superposed, cov- 
ered by the petiole base. Ptelea. (18). 

67. Base of petiole covering the axillary buds, or if not, 

the petioles and stems prickly; sometimes with stipular 
spines. 68. 

67. Base of petiole not covering the axillary buds; not spiny 

or prickly. 70. 

68. Leaflets entire. 69. 

68. Leaflets serrate or dentate, simply pinnate; pith very 
large; bark resinous or milky. Rhus. (54). 

68. Leaves serrate, bipinnate; petioles and stems prickly. 

Aralia. (78). 

69. Leaflets mucronate, usually obtuse; with stipular 

spines; base of petiole solid. Robinia. (45). 

69. Leaflets abruptly acute ; without stipular spines ; base 

of petiole covering the buds like a. cap. 

Cladrastis. (44). 

70. Leaflets entire or if occasionally few -toothed then the 

rachis prominently winged. 71. 

70. Leaflets serrate, dentate, or lobed, the rachis not winged. 

72. 

71. Leaflets decidedly inequilateral, obliquely lanceolate 

or falcate, acuminate. Sapindus. (50). 

71. Leaflets not inequilateral or only slightly so, not slender 
falcate, the rachis winged ; twigs pubescent. 

Rhus. (54). 



20 


Field Manual 


71. Leaflets not inequilateral or only slightly so, not slender 

falcate; rachis not winged; twigs glabrous. 

Toxicodendron. (55). 

72. Pith 5-angled; stipules none, base of petiole with numer- 

ous vascular bundles, scattered or in 3 areas. 

Carya. (73). 

72. Pith not 5-angled; stipules none; leaflets more or less 

lobed; vascular bundles in base of petiole scat- 

tered; terminal bud absent. Koelreuteria. (51). 

72. Pith cylindrical or nearly so; leaves with stipules; 

vascular bundles in base of petiole 3-5. 

Sorbus. (35). 

73. Pith small; base of petiole covering the axillary 

buds; usually with prominent thorns. 

Gleditsia. (42). 

73. Pith very large, base of petiole not covering the axil- 
lary buds; without thorns. Gymnocladus. (41). 


— 74— 


74. Leaves simple. 78. 

74. Leaves compound. 75. 

75. I.eaves digitate with 5 or more leaflets. 

Aesculus. (52). 

75. Leaves trifoliate or pinnate. 76. 

76. Base of petiole covering the axillary buds; leaflets 

dentate, lobed, or nearly entire. Acer. (53). 

76. Base of petiole not covering the axillary buds. 77. 

77. Leaves trifoliate; bark with strong odor; terminal 

bud self-pruned. Staphylea. (49). 

77. Leaflets 5-13; terminal bud present., Fraxinus. (30). 

78. Leaves pinnately veined. 82. 

78. Leaves palmately veined or at least with 2 prominent 

side ribs from the base. 79. 

79. Leaves entire or if somewhat 3-Iobed with entire mar- 

gin. 80. 

79. Leaves serrate, crenate, dentate or variously lobed. 81. 

80. Pith diaphragmed, or with large cavities; petioles 

usually hollow; axillary buds superposed. 

Paulownia. (31). 



Trees of the Northern United States 


21 


80. Pith and petioles solid; axillary buds not superposed; 

under side of leaves with glands in the axils of the 
large veins. Catalpa. (32). 

81. Leaves more or less lobed; fruit a 2-winged samara. 

Acer. (53). 

81. Leaves not lobed; fruit a drupe. Rhamnus. (46). 

82. Leaves serrate, dentate, crenate, or variously lobed. 83. 

82. Leaves entire. 85. 

83. Bark of ripe twigs green, bundle scar or vascular 

bundle in base of petiole 1; pith rhombic. 

Euonymus. (47). 

83. Bark of ripe twigs gray, brown, or red; pith cylindrical 

or nearly so. 84. 

84. Axillary buds sometimes superposed; leaves finely 

denticulate; twigs light brown, sometimes thorny; 
drupe narrowly oblong. Forestiera. (29). 

84. Axillary buds not superposed; twigs not 4-angled, brown; 
flowers epigynous; fruit a fleshy drupe; vascular 
bundles in the base of petiole 3. 

Viburnum. (83). 

84. Axillary buds not superposed; leaves serrate with 

stipules, small; bundle scar central; twigs brown, 
sometimes with thorns; shrub-like trees with 
drupe-like berries. Rhamnus. (46). 

85. Leaves coriaceous, evergreen, hence on wood of the 

previous season. Kalmia. (22).. 

85. Leaves deciduous each year. 86. 

86. Leaves with two outer lateral veins more or less parallel 

with the midrib. 87. 

86. Leaves pinnately veined to the tip. 88. 

87. Axillary buds not covered by the petiole base; in- 

florescence cymose. Cornus. (80). 

87. Axillary buds minute, hidden by the petiole base; 

flowers in involucrate heads. Cynoxylon. (81). 

88. Stipules none; fruit an oblong drupe. 

Chionanthus. (28). 

88. Stipules present; fruit dry, in a head. 

Cephalanthus. (82). 



KEY TO THE GENERA OF TREES IN THE 
WINTER CONDITION 


Based mainly on twig stem characters. The number fol- 
lowing the generic name refers to the list number. 

1. Foliage leaves persistent and usually evergreen. 2. 

1. Foliage leaves deciduous each year. 11. 

2. Foliage leaves needle-shaped, subulate, narrowly linear, 

or scale-like ; conifers. 3. 

2. Foliage leaves with expanded blades, netted veined. 8. 

3. With dwarf branches, each bearing 2-5 foliage leaves. 

Pinus. (7). 

3. Without true dwarf branches. 4. 

4. Leaf buds scaly. 5. 

4. Leaf buds not scaly, naked. 7. 

5. Leaf scar not on a sterigma, prominent, circular; 

leaves flat. Abies. (5). 

5. Leaf scar on a sterigma, the base of the leaf remaining 

as a scale on the twig. C. 

6, Leaves flat, those on the upper side of the twig 

much shorter than the lateral ones. Tsuga. (4). 

6. Leaves more or less 4-sided, spreading in all directions. 

Picea. (3). 

7. Foliage leaves small, scale-like, appressed, opposite, 

4-rankcd, closely covering the twigs which are 
decidedly flattened and fan-like; leaves of two 
shapes, the dorsal and ventral broader and less 
acute than the lateral ones; scales of the carpellate 
cone not peltate. Thuja. (8). 

7. Foliage leaves small, scale-like, appressed, opposite, 
4-ranked, usually much elongated, on somewhat 
flattened branches; scales of the carpellate cone 
4-6, the two upper fertile, not peltate. 

Eibocedrus. (9). 

7. Foliage leaves small, scale-like, appressed, opposite, 4- 
ranked, closely covering the slightly flattened twigs 
which are not very fan-like; leaves nearly or quite 
similar; scales or the carpellate cone peltate. 

Chamaecyparis. (10). 


( 22 ) 



Trkes of the Northern United States 


23 


7. Foliage leaves of two types, scale-like and subulate, 

opposite or in threes; the scale-like leaves 4-ranked, 
appressed, causing the twigs to appear quadran- 
gular, the subulate leaves spreading; one or both 
types of leaves on a plant; carpellatc cone develop- 
ing into a bluish-black, berry-like fruit. 

Juniperus. (11). 

8. Leaves with spine-tipped lobes or teeth. Ilex. (48). 

8. Leaves without spines. 9. 

9. Leaves pubescent at least below, lanceolate, mu- 

cronate, not evergreen ; buds clustered at the tip of 
the twig; trees with 5-angled pith. Quercus. (66). 

9. Leaves glabrous below; pith not 5-angled. lO. 

10. Leaves green on both sides, thick, coriaceous, oblong 
to oblanceolate, 5-10 in. long; winter buds very scaly. 

Rhododendron. (21). 

10. Leaves green on both sides or glaucous beneath, co- 
riaceous, 2-5 in. long, oval to oval-lanceolate; win- 
ter buds naked; erect shrubs. Kalmia. (22). 

10. Leaves bright green above, paler beneath, coriaceous, 4-5 

in. long, pointed at both ends ; bark aromatic. 

Persca. (15). 

— 11 — 

11. Twigs with thick wart-like dwarf branches; gymno- 

sperms. 12. 

11. Twigs without true dwarf branches. 13. 

12. Young twigs covered with scales. Larix. (6). 

12. Twigs without scales. Ginkgo. (1). 

13. Twigs with numerous small scattered self-pruning scars, 

without apparent leaf scars but with minute dry scale 
leaves, with feather-like dwarf branches, some usually 
remaining in winter; roots often with knees; a conifer. 

Taxodium. (2). 

13. Twigs with evident leaf scars and lateral winter buds. 14. 

14. Leaf scars alternate. 15. 

14. Leaf scars opposite or whorled. 72. 

15. Twigs with distinct and complete stipular ridges or rings 

at the leaf nodes. 16, 

15. Twigs without complete stipular rings. 18. 



24 


Field Manual 


16. Leaf scar surrounding the axillary bud, terminal bud 

self -pruned; wood with prominent medullary rays. 

Platanus. (59). 

16. Leaf scar not surrounding the axillary bud, terminal bud 

not self-pruned; buds enclosed in the large connate 

stipules. 17. 

17. Buds glabrous; twigs brown; pith diaphragmed; leaf 

scars oval or circular; bark spicy-aromatic. 

Liriodendron. (13). 

17. Buds downy, or if glabrous then the twigs red; pitch with 

or without diaphragms; leaf scars U-shaped, oval, or 
circular; bark usually aromatic. 

Magnolia. (12). 

18. With thorns, prickles, or spines ; or with spur-like 

branches ending in thorns. 19. 

18. Without thorns, prickles or spines, but some may have 

thorn-like stunted branches. 26. 

19. With stipular spines, a pair for each leaf scar. 20. 

19. Twigs with typical lateral thorns, without terminal 
thorns. 21. 

19. With thorns at the ends of branches or with spur-like 
branches ending in thorns, and in addition axillary 
thorns may be present. 22. 

19. Stems or twigs with prickles; leaf scar extending 

nearly around the stem, with about 20 bundle 
scars; pith large. Aralia. (78). 

20. Leaf scar covering the two or more superposed axil- 

lary buds. Robinia. (45). 

20. Leaf scar below the axillary buds; buds reddish, pu- 

bescent. Zanthoxylum. (17). 

2L With thorns beside the axillary buds; normally one 
for each leaf axil, becoming gradually smaller to- 
ward the tip of the twig, terminal bud absent. 

Madura. (65). 

21. Thorns axillary, large, rarely branched except on the 

main trunk; usually with two lateral buds at the 
base which may develop as twigs; numerous axils 
without thorns. Crataegus. (40). 



Trees of the Northfjin United States 


21. Thorns commonly branched, situated above the axil of 

the leaf; leaf scar covering the two or more superposed 
axillary buds ; twigs polished, often zigzag. 

Glcditsia. (42). 

22. Not with three distinct bundle scars. 23. 

22. With three bundle scars. 24. 

23. Buds and twigs glabrous or nearly so ; with few thorns. 

Rhamnus. (46). 

23. Buds and sometimes twigs pubescent or downy; 

thorns prominent. Bumelia. (24). 

24. Terminal bud self-pruned; twigs some shade of black, 

brown, or reddish. Prunus. (33). 

24. Terminal bud present. 25. 

25. Buds conical, pungent, pubescent, twigs glabrous or 

nearly so, mostly yellow-olive; trees with erect 
growth the branches not spreading as in most of 
the apples. Pyrus. (37). 

25. Buds downy or pubescent, twigs usually pubescent, 

if glabrous then dark reddish-brown; trees with 
rounded crowns and spreading branches. 

Malus. (36). 

— 26 -~ 

26. Leaf scars quite regularly 2-ranked, that is with the third 

scar over the first. 27. 

26. Leaf scars not 2-ranked. 38. 

27. Terminal bud present. 28. 

27. Terminal bud absent, the twig showing a terminal self- 

pruning scar at the morphological tip. 31. 

28. Terminal bud naked, prominently stalked or elongated and 

silky. 20. 

28. Terminal bud with dry scales, not stalked nor silky. 30. 

29. Terminal bud not stalked, silky; pith diaphragmed, 

solid. Asinaina. (14). 

29. Terminal bud prominently stalked, tomentose; pith 

not diaphragmed; twigs zigzag. Hamamelis. (57). 

30. Medullary rays not prominent; visible bud scales 

few; bundle scars 3. Amelanchier. (39). 



26 


Fieli> Manual 


30. Medullary rays very prominent; visible bud scales 
numerous; bundle scars more than 3. 

Fagus. (68). 

30. Medullary rays not prominent; visible bud scales 2; 

bundle scar 1. Diospyros. (25). 

31. Pith interruptedly diaphragmed, with cavities, small, 

greenish-white. Celtis. (60). 

31. Pith solid. 32. 

32. Twigs dark reddish-brown, speckled, often zigzag ; buds 

reddish-violet, often superposed or clustered. 

Cercis. (43). 

32. Twigs not speckled as above but the pith 5-angled. 

Castanea. (67). 

32. Twigs not speckled; pith cylindrical or nearly so. 33. 

33. Medullary rays very prominent in tangential section; 

winter buds usually long pointed with several to 
many dry scales. Fagus. (68). 

33. Medullary rays very prominent; winter buds rather 
fleshy, usually with 1-3 visible scales. 

Tilia. (20). 

33. Medullary rays inconspicuous. 34. 

34. Bundle scars more than 3, definitely scattered. 35. 

34. Bundle scars 3, or if more than the petiole base with a 

double abscission, a small joint abscissed from the pro- 
jecting petiole base and exposing more than 3 bundle 
scars. 36. 

35. Visible bud scales more than 3; twigs glabrous or 

pubescent but not downy. Morus. (63). 

35. Visible bud scales 1-3; twigs downy, grayish-green; 

bark very fibrous. Broussonetia. (64). 

36. Bark smooth, trunk and large branches with pecu- 

liar fluted or projecting ridges; bud scales brown, 
finely pubescent; staminate catkins in the bud in 
winter; with double abscission in the petiole base. 

Carpinus. (69). 

36. Trunk not with fluted or projecting ridges. 37. 

37. Bark of trunk scaling oflP like in the Sycamore; twigs 

very slender; no catkins. Planera. (61). 

37. Bark in rough ridges; no catkins; twigs and buds in 
most cases pubescent; some species with charac- 



TRI<a2S OF THE NORTHERN UNITED STATES 


27 


teristic transverse self-pruning scars on the twigs, 
others with corky ridges. Ulmus. (62). 

37, Bark scaly, fine-furrowed, the furrows usually some- 
what spiral; bud scales green with brown tips, 
nearly glabrous; twigs glandular-bristly; staminate 
catkins exposed in winter; with double abscission 
in the petiole base. Ostrya. (70). 

37. Bark of trunk and larger branches separating into papery 

or leathery sheets ; catkins in winter. 

Betula. (71). 

— 38 — 

38. With 2 or more superposed axillary buds ; all except 1 

may be very small. 39. 

38. Axillary buds single or 2 or more side by side ; not super- 

posed. 46. 

39. Pith diaphragmed, with air cavities. 40. 

39. Pith diaphragmed but solid; bundle scars 3; stipular 
scars none. Nyssa. (79). 

39. Pith not diaphragmed, solid. 41. 

40. Pith large, brown; twigs thick, with large leaf scars 

and 3 prominent bundle scars. Juglans. (74). 

40. Pith rather small, white or greenish; leaf scars semi- 

circular; outer bud scales about 2. Halesia. (27). 

41. Buds partly sunken, hardly projecting beyond the surface 

or if so pith very large; terminal bud self-pruned or 
tips of branches withering. 42. 

41. Buds not sunken in the epidermis. 43. 

42. Leaf scar not surrounding the axillary buds; pith 

large, chocolate-colored; twigs robust, polished, 
mottled white and purplish-brown. 

Gymnocladus. (41). 

42. Leaf scars not surrounding the buds; pith large, 
white or brown; twigs brown, not mottled, pubescent. 

Ailanthus. (19). 

42. Lear scar surrounding the axillary buds, quadrangular 
U-shaped; bark with pungent odor; pith white. 

Ptelca. ( 18 ). 

42. Leaf scar covering the axillary buds; pith small; twigs 
brown, polished, often zigzag. Gleditsia, (42). 



Field Manual 


2S 

43. Pith cylindrical or nearly so. 44. 

43. Pith more or less 5-ang-led, yellowish or brownish; 

terminal bud large; bundle scars scattered; trees 
with tough twigs. Carya. (73).. 

44. Leaf scar surrounding the hairy axillary buds; bun- 

dle scars 5-9; terminal bud self-pruned. 

Cladrastis. (44). 

44. Leaf scar not surrounding the axillary buds. 45. 

45. Bundle scars 3 ; buds spherical, bark light gray ; leaf scars 

heart-shaped; stipular scars none. 

Sapindus. (SO). 

45. Bundle scar usually 1 ; buds rounded or somewhat pointed ; 

stipular scars or minute stipules present. 

Ilex. (48). 

— 46 — 

46. Terminal and lateral buds stalked; pith 3-angled; both 

staminate and carpellate catkins present all winter. 

Alnus. (72). 

46. Buds sessile or nearly so; pith not 3-angled. 47. 

47. Leaf scars surrounding the axillary buds which are 

usually sunken; terminal bud self-pruned; bark 
resinous; pith large. Rhus. (54). 

47. Leaf scars not surrounding the axillary buds. 48. 

48. Bundle scar 1, or if several then closely crowded and 

confluent, appearing as 1. 49. 

48. Bundle scars more than 1. 54. 

49. Stipular scars and stipules present. 60. 

49. Stipular scars and stipules none. 51. 

50. Terminal bud absent; bud scales dark brown or 

black. Rhamnus. (46). 

50. Terminal bud present; stipules minute, usually per- 

sistent. Ilex. (48). 

51. Terminal bud present. 50, 

51. Terminal bud absent. 53. 

52. Pith diaphragmed, with cavities; bark reddish; outer 
bud scales several, short. Symplocos. (26). 

52. Pith not diaphragmed; bark green, very spicy aro- 
matic; internodes very unequal. Sassafras. (16). 



Trees of the Northern United States 


29 


53. With polished, greenish-brown, grayish-yellow, or 
red twigs; bark sour; leaf scar prominent, semi- 
oval, with a dark central scar usually in the form 
of a ring; buds small, not projecting much beyond 
the epidermis; the large terminal panicled raceme 
with capsules persisting all winter. 

Oxydendrum. (23). 

53. With 2 visible scales in the triangular flattened bud; 

pith sometimes with cavities; twigs pubescent or 
glabrous; zigzag; at the tip. Diospyros. (25). 

— 54-- 

54. Outer bud scales more than 1. 55. 

54.. Outer bud scale 1; twigs usually with brittle zones 
and hence very easily detached; stipular scars pres- 
ent; bundle scars 3; pith small. Salix. (77).. 

55. Pith diaphragmed but solid; bundle scars 3; no stip- 

ular scars. Nyssa. (79). 

55. Pith not diaphragmed. 56. 

56. Pith more or less 5-angled. 57. 

56. Pith cylindrical or nearly so. 61. 

57. Buds clustered at the tip of the twig; bundle scars 

numerous, scattered. Quercus. (66). 

57. Buds not clustered at the tip. 58. 

58'. Bundle scars numerous usually scattered. 59. 

58. Bundle scars 3. 60. 

59. Buds small with about 3 outer scales ; twigs reddish 

or yellowish-brown, glabrous or pubescent ; terminal 
bud present or absent; stipular scars prominent. 

Castanea. (67). 

59. Terminal bud large with 4 or more visible scales, 

hairy or peltate pubescent; lateral buds usually su- 
perposed; twigs tough. Carya. (73). 

60. Without stipular or self-pruning scars; crushed buds 

fragrant, aromatic, not resinous, glabrous. 

Liquidambar. (58). 
60. Stipular and self-pruning scars present; crushed buds 
not fragrant though they may have a resinous 
odor, resinous or if only slightly so then the twigs 
pubescent or tomentose. Populus. (76). 



30 


Field Manual 


61. Pith very large, light brown, bark not resinous, ill-smell- 
ing; buds spherical or flattened at the apex, often 
clustered at the tip of the twig, brown and pubescent ; 
bundle scars about 9 along the lower edge of the 
very large leaf scar ; large trees. 

Ailanthus. (19). 

61. Pith small, or if large and brown then the bark resin- 

ous. 62. 

62. Bark with a resinous or sticky milky sap; pith usually 

large, if rather small then the bark aromatic. 63. 

62. Bark not resinous. 64. 

63. Buds clustered at the tip of the twig ; bark spicy- 

fragrant to the smell ; base of petiole prominent with 
several bundle scars; fruiting panicles plumose. 

Cotinus. (56). 

63. Buds not clustered at the tip; bark, often very poi- 

sonous to the touch; leaf scar partly surrounding 
the bud; small trees or shrubs. 

Toxicodendron. (55). 

64. Terminal bud absent. 65. 

64. Terminal bud present. 68. 

65. Stipules or stipular scars absent or indistinct. 66. 

65. Stipules or stipular scars present. 67. 

66. Buds clustered at the tip of the twig; young twigs 

glandular dotted. Myrica. (75). 

66. Buds not clustered at the tip; twigs not glandular; 
bundle scars 3. Prunus. (33). 

66. Buds not clustered at the tip ; twigs not glandular ; bundle 

scars numerous ; outer bud scales 2. 

Koelreuteria. (51). 

67. Buds and twigs very downy, twigs dark brown or black. 

Cydonia. (38). 

67. Buds downy or pubescent; twigs glabrous or pubes- 

cent, gray or brown. Hhamnus. (46). 

68. Twigs green or yellowish-green, glabrous; internodes very 

unequal ; lateral buds minute ; small trees. 

Cornus. (80). 

68. Twigs normally red above and green beneath, gla- 
brous; bark very bitter; some axils with 2 or 3 hairy 
buds of nearly equal size; trees. Amygdalus* (34). 



Trees of the Northern United States 

C8. Twigs not green or red and green unless the plants are 
low shrubs, but gray, brown, black, or reddish. 69. 

69. Bundle scars 5 or more in the broad U-shaped leaf scar ; 
tips of the buds quite downy ; small trees. 

Sorbus. (35). 

69. Bundle scars 3. 70. 

70. Buds rounded at the apex, often clustered at the tip 

of the twig; twigs glandular dotted. Myrica. (75). 

70. Buds rounded at the apex; scales thick; twigs often 
zigzag ; plant usually with some thorns, not glan- 
dular dotted. Crataegus. (40). 

70. Buds pointed ; plants sometimes with thorn-like stunted 

branches, not glandular dotted. 71. 

71. Buds glabrous or slightly pubescent; twigs usually 

glabrous and slender, some shade of black, brown, 
or reddish, often with 2 or 3 axillary buds; some 
with self-pruning scars. Prunus. (33). 

71. Buds long-pointed, the scales rather thick; twigs 
somewhat pubescent; leaf scars narrow, contracted 
between the bundle scars. Amelanchier. (39). 

71. Buds downy or strongly pubescent, conical, pungent; 
twigs glabrous, mostly yellow-olive; trees with 
erect growth, the branches not spreading as in 
most of the apples, Pyrus. (37). 

71. Buds downy or strongly pubescent; twigs strongly 
pubescent or if glabrous then dark reddish-brown; 
trees with rounded or spreading crowns. 

Malus. (36). 

71. Buds and twigs very pubescent; terminal bud with long 

spreading scales; shrubs or small trees with globose 
berry-like drupes containing 2-4 stones. 

Rhamnus. (46). 

— 72 — 

72. Bundle scars 1, or several closely united in a curved 

line, appearing as 1, 74. 

72. Bundle scars more than 1 but not in an ellipse or ring. 78. 

72. Bundle scars numerous, in an ellipse or ring; buds small 
and flat or superposed, pith large. 73. 



32 


Field Manual 


73. Pith with cavities or more or less diaphragmed; axil- 
lary buds superposed. Paulownia. (31)., 

73. Pith solid; axillary buds small and flat, not super- 

posed, leaf scars often in threes. Catalpa. (32). 

74. Twigs very green, more or less 4-angled; pith di- 

amond-shaped or rhomboidal. Euonymus. (47). 

74. Twigs not green when ripe but gray, brown or red, 

sometimes 4-angled; pith cylindrical or nearly so. 75. 

75. Terminal bud absent, the twig usually ending in a 

thorn. Rhamnus. (46). 

75. Terminal bud present unless the twig is fruiting. 76. 

76. Axillary buds often superposed; twigs often with 

thorns; leaf scars small. Forestiera. (29). 

76. Axillary buds not superposed ; no thorns on the twigs ; 

leaf scars rather large. 77. 

77. Twigs and buds pubescent; lateral buds cylindrical 

or heimspherical; bud scales dry; leaf scar con- 
cave, on the short petiole base; lenticles large and 
conspicuous; fruit a drupe. Chionanthus. (28). 

77. Buds rough or pubescent; twigs glabrous or pubescent, 
sometimes 4-angled ; lateral buds somewhat flattened, 
obtuse; bud scales rather dry; leaf scar close to the 
bark; lenticles not large; fruit a samara. 

Fraxinus. (30). 

77. Axillary buds minute and sunken; twigs glabrous or 

pubescent; stipules dry, prominent; or with promi- 
nent stipular scars. Cephalanthus. (82), 

78. With 4 distinct stipular scars; terminal bud self- 

pruned; twigs green with strong odor. 

Staphylea. (49). 

78. Without definite stipular scars; twigs not green or if so 

then the terminal bud present. 79. 

79. Trees or shrubs with numerous bundle scars, some- 

times in 3 areas, in a large heart-shaped leaf scar; 
pith rather large; terminal bud large, with nu- 
merous scales. Aesculus. (52). 

79. Bundle scars 3 or sometimes 5. 80. 

80. Terminal bud with 2 long acuminate pubescent outer 

scales ; line connecting the uppermost leaf scars notched. 

81. 



Trees of the Northern United States 




80. Terminal bud with one main pair of visible scales 
and a smaller pair at the base. Viburnum* (83). 

80. Terminal bud with several pairs of visible scales ; bundle 

scars 3-5; twigs sometimes green. Acer. (53). 

81. Axillary buds usually minute and undeveloped ercept at 

the base of the peduncle which is self-pruned; twigs 
green or reddish-green, glabrous or nearly so. 

Cynoxylon. (81). 

81. Axillary buds normally well developed and promi- 
nent; twigs often very pubescent. Cornus. (80). 



GENERAL KEY TO THE FAMILIES AND GENERA 


Rased on the flower and other characters present at the 
time of blooming. The number following the generic name 
refers to the list number. 

1. Ovules naked on an open carpel ; pollen falling directly 
on the micropylc of the ovule which is mostly without 
a pollen-chamber ; trees or shrubs ; ours usually ever- 
green with narrow leaves ; monecious, rarely diecious. 2 . 

1. Ovules' in a closed carpel or set of carpels provided with 

a stigma for the reception of the pollen ; flowers more 
commonly showy. 4. 

2. Leaves fanshaped, dichotomously veined, on thick wart- 

like dwarf branches; diecious trees. Ginkgoaceae. 

a. Ginkgo. (1). 

2. Leavers not fanshaped and dichotomously veined, but 

needle-shaped, narrowly linear, subulate or scale-like. 3. 

3. Leaf buds naked or minute ; carpels few, spiral ; leaves on 

feather-like dwarf branches which are deciduous. Taxo- 
diaceae. 

a. Taxodium. (2). 

3. Leaf-buds naked ; carpels few, opposite, sometimes form- 
ing a black or blue berry-like fruit ; leaves opposite or 
whorled, rarely scattered, persistent. Juniperaceae. 

a. Carpel late cones oblong, the scales not peltate, b. 

a. Carpel late cones globose or nearly so, the scales pel- 

tate, or forming a bluish berry-like fruit, c. 

b. Cone scales 6-10, the upper fertile. Thuja. (8). 

b. Cone scales 4-6, the 2 upper fertile. 

Libocedrus. (9). 

c. Cone with dry peltate scales; ovules usually 2. 

Chamaecyparis. (10). 

c. Cone becoming blue and fleshy ; twigs not flattened ; 
leaves or some of them often subulate. 

Juniperus. (11). 


( 34 ) 



Trkes of the Northern United States 3^) 

3. Leaf-buds scaly ; carpels usually numerous ; leaves spirally 
arranged, the foliage leaves often situated on dwarf 
branches. Pinaceae. 

a. Without dwarf branches, b. 

a. With dwarf branches, d. 

b. Leaf scar on a sterigma, the twigs covered with scales 

representing the leaf bases, c. 

b. Leaf scars on the bark; twigs without scales; leaves 

usually flat ; carpellate cones erect. 

Abies. (5). 

c. Leaves more or less 4-sided, spreading in all direc- 

tions; carpellate cones pendulous. Picea. (3). 

c. Leaves flat, those on the upper side of the twig much 

shorter than the lateral ones; carpellate cones 
small, pendulous. Tsuga. (4). 

d. Leaves deciduous, numerous on thick, wart-like 
dwarf branches. Larix. (6). 

d. Leaves needle-shaped, persistent, 2-7 on small 
self-pruned dwarf branches. Pinus. (7). 

--4 — 


4. Leaves mostly parallel-veined, sometimes netted-veined ; 
parts of the flower very often in threes (trimerous) ; 
cotyledon 1 ; the closed vascular bundles scattered 
through the pith, usually not in a circle ; no annual 
rings of growth. No trees in our region. Monocot ylae. 

4. Leaves usually netted-veined; parts of the flower more 

commonly in fives (pentamerous) or fours (tetramer- 
ous) ; cotyledons usually 2; vascular bundles usually in 
a circle around a central pith, forming annual rings 
of growth in perennial stems, with bark on the outside. 5. 

5. DICOTYLAE. 

5. Perianth none or of similar segments or divided into calyx 

and corolla; corolla when present choripetalous (petals 
<ristinct), sepals, petals and stamens sometimes on a 
disk or hypanthium. 6. 



36 


Field Manual 


5. Perianth composed of calyx and corolla, calyx may be 

minute or suppressed; corolla sympetalous (petals more 
or less united). 39. 

6. Calyx and corolla both present, calyx may be minute. 7. 

6. Only the calyx present, sepals distinct or united green or 

colored ; or perianth none. 25. 

7. Flowers hypogynous or perigynous ; ovulary free or only 

slightly adherent to the perigynous disk or hypanthium. 

8 . 

7. Flowers epigynous or apparently epigynous ; calyx above 

the ovulary, with or without an hypanthium. 24. 

8. Stamens numerous, at least more than 10 and more than 

twice the petals. 9. 

8. Stamens not more than twice as many as the petals, when 
of just the number as the petals then alternate with 
them. 12 

8. Stamens of the same number as the petals and opposite 

them ; ovulary 2-5-locular, calyx 4-5-cleft, valvate in the 
bud; petals involute; fruit a drupe or capsule; shrubs, 
small trees, or vines with simple leaves. Rhamnaceae. 

a. Rhamnus. (46). 

9. Carpels 1 or more, united, but styles and stigmas may be 

several, 10. 

9. Carpels more than 1, distinct; filaments shorter than the 
anthers ; perianth trimerous ; leaves 2-ranked. 

Anonaceae. 

a. Asimina. (14). 

9. Carpels numerous spirally arranged and cohering over 
each other, forming an aggregate conc-like fruit ; trees ; 
sepals and petals in threes; twigs with stipular rings. 

Magnoliaceae 

a. Anthers introrse ; leaves not truncate. 

Magnolia. (12) 

a. Anthers extrorse ; leaves truncate. 

Liriodendron. (13). 

lO. Ovulary compound plurilocular, 11. 

10. Ovulary unilocular, 2-ovuled; leaves usually with disk- 
like or tooth-like glands on the petiole or at the base 
of the blade. Rosaceae. (Amygdalatae). 



Trees of the Northern United States 


37 


a. Young ovulary and drupe glabrous. 

Pninus. (33). 

a. Young ovulary and drupe velvety-pubescent. 

Amygdalus. (34). 

11. Flower cluster subtended by a large, membranous bract; 
calyx deciduous ; leaves alternate 2l-rankcd ; sap mu- 
cilaginous. Tiliaceae. 

a. Tilia. (20). 

11. Flowers not subtended by a membranous bract; leaves 

alternate with deciduous stipules ; sepals persistent. 
Ros aceae. ( M alatae) . 

See 24 below. 

12. Ovulary only 1, carpels 1 to many, united, lb. 

12. Carpels 2 or more, distinct, or somewhat united at the 

base. 13. 

13. Leaves compound. 14. 

13. Shrubs or trees with alternate simple leaves. Hama- 

MEJ.IDACEAE. 

a. Ovules 1 in each cavity; leaves inequilateral, not 
star-shaped. Hamamelis. (57). 
a. Ovules several in each cavity, fruit globular, spiny. 

Liquidambar. ( 46 ) . 

14. Leaves punctate with pellucid dots, alternate. Rutaceae. 

a. Zanthoxylum. (17). 

14. Leaves large, pinnate, alternate, not punctate but with 

disk-like glands under the teeth or lobes. Simakubaceae. 

a. Ailanthus. (19). 

15. Carpel 1, ovulary with 1 parietal placenta; leaves alternate, 

usually with stipules; usually compound. Fabaceae. 

A. Upper petal inclosed by the lateral ones in the bud; 
leaves simple or compound mostly with stipules. 
Cassiatae. 

a. Leaves simple, flowers bisporangiate. 

Ccrcis. (43). 

a. Leaves compound, flowers diecious or imperfectly 
diecious. b. 



38 


Field Manual 


b. Stamens 3-5; pith small; usually with thorns. 

Gleditsia. (42). 

b. Stamens 10 ; pith large, chocolate - colored ; 
without thorns. Gymnocladus. (41). 

B. Upper petal inclosing the lateral ones in the bud; 
leaves compound (sometimes with 1 leaflet) with 
stipules. Fauatae. 

a. Without stipular spines; leaflets large, 3-6 in. 
long ; base of petiole covering the axillary 
buds like a cap.. Cladrastis. (44). 
a. With stipular spines; leaflets small, 1-2 in. long; 
base of petiole not covering the axillary buds 
like a cap, but solid. Robinia. (45). 

15. Carpels more than 1 as shown by the compound ovu- 

lary cavities, placentae, styles, or stigmas. 16. 

16. Ovulary 2-locular to pluriocular. 17. 

16. Ovulary 1-locular, ovules solitary, stigmas 3; shrubs or 

trees with resinous or milky sap and alternate leaves 
without stipules. Anacardiaceae. 
a. Leaves compound; style terminal, b. 

a. Leaves simple; style lateral. Cotinus. (56). 

b. Petiole base covering the axillary buds, or if not then 

the rachis wing-margined; not poisonous. 

Rhus. (54). 

b. Petiole base not completely covering the axillary 
buds, the rachis not wing-margined; poisonous to 
the touch; glabrous; leaflets entire. 

Toxicodendron. (55). 

17. Flowers regular or nearly so. 18. 

17. Flowers irregular; shrubs or trees with opposite digitate 
leaves ; ovulary 3-locular. Aesculaceae. 

a. Aesculus. (52). 

17. Flowers irregular in the number of the several floral 

sets ; leaves pinnate or bipinnate, alternate ; ovulary 
3-locular. Sapindaceae. 

a. Koclreuteria. (51). 

18. Stamens neither just as many nor twice as many as the 

petals. 1&. 



Trees of the Northern United States 39 

18. Stamens just as many or twice as many as the petals. 20. 

19. Stamens distinct and fewer than the 4 petals ; trees or 

shrubs with opposite pinnate or simple leaves. Oleaceae. 
a. Pdowers diecious, from catkin-like scaly buds. 

Forestiera. (29). 

a. Flowers bisporangiate petals linear. 

Chionanthus. (28). 

19. Stamens more numerous than the petals; leaves palmately 

veined, opposite; fruit 2- winged. Some Aceraceae. 

a. Acer. (53). 

20. Ovules 1 or 2 in each cavity. 21. 

20. Ovules several or many in each cavity ; stipules between 

the opposite and pinnately compound leaves, caducous ; 
shrubs or small trees. Staphyleaceae. 

a. Staphylea. (49). 

21. Leaves palmately veined, or compound. 22. 

21. Leaves pinnately veined, simple, not punctate. 23. 

22. Leaves pinnately compound, alternate ; ours trees with a 

globose or lobed berry. Sapindaceae. 

a. Sapindus. (50). 

22. Leaves palmately veined or pinnately compound ; trees 
or shrubs with opposite leaves and no stipules. Acer- 
aceae. 

a. Acer. (53). 

22. Leaves 3-foliate, pellucid-punctate, without stipules. Some 

Rutaceae. 

a. Ptelea. (18). 

23. Calyx minute; trees or shrubs with simple mostly alter- 

nate leaves. Ilicaceae. 

a. Ilex. (48). 

23. Calyx not minute; trees, shrubs, or woody climbers; ours 
with opposite leaves and with minute fugaceous stipules. 
Celastraceae. 


a. Euonymus. (47). 



Field Manual 


— 24-- 

Perfect stamens 4, styles 2; leaves alternate, palmately 
veined and lobed, or if pinnately veined then 2->ranked. 
Hamamelidaceae. 

See 13 above. 

Stamens 5, 10 or many ; styles 2-5 ; leaves alternate with 
stipules. Rosaceae. (Malatae). 

a. Leaves pinnate. Sorbus. (35). 

a. Leaves simple, b. 

b. Cavities of the ovulary as many as the styles, c. 

b. Cavities of the ovulary becoming twice as many as 

the styles. Amelanchier. (39). 

c. Ovules many in each cavity (carpel). 

Cydonia. (38). 

c. Ovules 1-3 in each cavity of the ovulary. d. 

d. Usually with typical thorns; ripe carpels bony. 

Crataegus. (40). 

d. Without thorns, but some may have thorn-like stunted 

branches; ripe carpels papery or leathery, e. 

e. Leaves sharply and regularly serrate, glabrous when 

mature, petioles long; pome with grit cells. 

Pyrus. (37). 

e. Leaves irregularly dentate or serrate, or more or less 
lobed; pome without grit cells. Malus. (36). 
Stamens 4 or 5, style and stigma 1 ; leaves opposite or 
alternate. Cornaceae. 

a. Ovulary 2-locular, flowers bisporangiate. b. 

a. Ovulary l-3ocular, flowers diecious or imperfectly 

diecious. Nyssa. (79). 

b. Flowers cymose, not involucrate. Cornus. (80). 
b. Flowers capitate, with an involucre of 4-6 large 

white bracts., Cynoxylon. (81). 

Stamens 4 or 5 on a flat disk which covers the 3-5-locular 
ovulary ; shrubs or trees with opposite leaves and minute 
fugaceous stipules. Celastraceae. 

See 23 above. 



Trees of the Northern United States 


41 


24. Stamens 5, styles usually 2-5; leaves bipinnate. Arali- 

ACEAE. 

a. Aralia. (78).. 

— 25 — 

25. Leaves opposite. 26. 

25. Leaves alternate. 27. 

2'G. Stamens 5-8; leaves palmately veined and simple or if 
pinnately compound then the base of the petiole cover- 
ing the axillary buds. Aceraceae. 

a. Acer. (53). 

26. Stamens 2-4 ; leaves pinnately veined w^hen simple, or 

if pinnately compound then the axillary buds exposed. 
Oleaceae. 

a. Flowers fasciculate or racemose- fasciculate not from 
prominent scaly buds ; leaves compound. 

Fraxinus. (30). 

a. Flowers fasciculate, from scaly buds; leaves simple. 

Forestiera. (29). 

27. At least the staminate flowers in catkins or catkin-like 

spikes or spherical heads. 31. 

27. Flowers not in catkins or catkin-like spikes or heads. 28. 

28. With prominent stipular spines; leaves punctate with 

glands. R utaceae. 

a. Zanthoxylum. (17). 

28. Without stipular spines. 29. 

29. Styles or stigmas 3 or 4; perigynous stamens, 4-5, alter- 

nate with the sepals; ovulary 2-5-locular, ovules soli- 
tary in each cavity. Rhamnaceae. 

a. Rhamnus. (46). 

39. Styles or stigmas 2; leaves 2-ranked; ovulary 1-2-ovuled; 
stipules fugaceous. Ulmaceae. 
a. Flowers in clusters on twigs of the previous season; 
pith not diaphragmed. b. 

a. Flowers on elongated twigs of the season ; pith 

interruptedly diaphragmed. Celtis. (60). 

b. Flowers expanding before the leaves; bark in rough 

ridges. Ulmus. (62). 



42 


Fieijd Manual 


b. Flowers expanding with the leaves; bark of trunk 
scaling off like in the Sycamore. Planera. (61). 

29. Style and stigma 1. 30. 

30. Calyx 6-parted; stamens and staminodes about 12 in 4 

series; bark spicy-aromatic. Lauraceae. 
a. Flowers bisporangiate, panicled ; leaves evergreen. 

Persca. (15). 

a. Flowers monosporangiate, racemose or umbellate; 
leaves deciduous, some of them lobed. 

Sassafras. (16). 

30. Calyx 5-parted ; stamens 10 or fewer ; bark not aromatic. 
Fabaceae. (Cassiatae.) 

See 15 above. 

30. Calyx 5-parted; stamens 5-15; flowers epigynous; pith 

solid but diaphragmed. Cornaceae. 

a. Nyssa. (79). 

31. Twigs with complete stipular rings; base of petiole cover- 

ing the axillary bud; flowers monecious, in dense heads. 
Platan aceae. 


a. Platanus. (59). 

31. Twigs without stipular rings. 32. 

32. Axillary buds superposed ; staminate flowers in flexible 

catkins ; leaves pinnately compound. Juglandaceae. 
a. Pith solid. Carya. (73). 

a. Pith diaphragmed, with cavities. Juglans. (74). 

32. Axillary buds not superposed or if so then the staminate 

flowers not in flexible catkins; leaves simple. 33. 

33. Carpellate flowers epigynous; pith solid, with diaphragms. 

Cornaceae. 

a. Nyssa. (79). 

33. Carpellate flowers hypogytious or perigynous ; pith not 

diaphragmed. 34. 

34. Staminate and carpellate flowers in dense spherical heads, 

sap not milky ; leaves star-shaped, fragrant when 
crushed. Hamamelidaceae. 

a. Liquidambar. (58). 

34. Staminate and carpellate flowers not in dense spherical 
heads unless the sap is milky ; leaves not star-shaped. 35. 



Trees of the Northern United States 


43 


35. With milky sap; leaves with two prominent lateral veins 
from the base or if not then the twigs thorny. Moraceae. 
a. Twigs with thorns; carpellate perianth deeply 4- 
clcft carpellate flowers capitate. Madura. (65). 

a. Twigs without thorns, b. 

b. Staminate and carpellate flowers in ament-like 

spikes. Morus. (63). 

b. Staminate flowers racemose or spikate the carpel- 
late capitate. Broussonetia. (64). 

35. Sap not milky. 30. 

30. Both staminate and carpellate flowers in aments, the car- 
pellate flowers not subtended by a bur or cup. 37. 

30. Carpellate flowers not in aments, subtended by a cup or 
involucre ; staminate flowers in flexible or somewhat 
capitate aments. Fagaceae. 
a. Staminate flowers capitate, ovulary 3-angled. 

Fagus. (68). 

a. Staminate flowers in slender aments, b. 

b. Carpellate flowers 2-5 in each involucre, which be- 

comes prickly. Castanea. (67). 
b. Carpellate flower 1 in each involucre, which con- 
sists of numerous scales. Quercus. (66). 

37. Ovulary 1-locular, many seeded; seeds with a tuft of 
cottony hairs. Salic aceae. 

a. Stamens numerous ; bracts fimbriate or entire, buds 
with several exposed scales; pith 5-angled. 

Populus. (76). 

a. Stamens 2-10; bracts entire; buds with 1 outer 
scale. Salix. (77). 

37. Ovulary 1-2 locular, with 1-2 ovules in each cavity; seeds 

not with cottony hairs. 38. 

38. Carpellate flowers single in the axils of the bracts ; young 

twigs and leaves glandular dotted ; buds clustered at 
the tip of the twig. Myricaceae. 

a. Myrica. (75). 

38. Carpellate flowers 2 or more in each bract of the ament; 
twigs and leaves not glandular dotted; buds not clus- 
tered at the tip of twig. Betulaceae. 



44 


Field Manual 


a. Pith 3-angled ; buds stalked ; leaves not 2-ranked ; 
stamens 4. Alnus. (72). 

a. Pith not 3-angIed; buds sessile; leaves 2-rankcd. b. 

b. Staminate flowers 3-6 in the axil of each bract, 

with a calyx; carpcllate flowers without a calyx; 
stamens 2. Betula. (71). 

b. Staminate flowers solitary in the axil of each bract, 

without a calyx; carpellate flower with a calyx. 

c. 

c. Fruiting bract flat, 3-cleft and incised; bark smooth; 

trunk and large branches with peculiar fluted or 
projecting ridges. Carpinus. (69). 
c. Fruiting bract bladder-like, closed; bark of older 
trunks scaly and fine-furrowed. Ostrya. (70). 

— SO- 
SO. Flowers hypogynous (ovulary superior). 40. 

39. Flowers epigynous (ovulary inferior). 44. 

40. Stamens free from the corolla (or only very slightly united 

at the base) as many as the petals (flowers tetracyclic) 
and alternate with them, or twice as many (pentacyclic) 
or more. 41. 

40. Stamens united with the corolla, as many as the petals 
and opposite them or twice as many or more. 42. 

40. Stamens united with the corolla, the fertile ones fewer 

than the petals and alternate with them. 43. 

41. Sympetalous trees or shrubs often with evergreen leaves 

without stipules. Ericaceae. 

a. Leaves deciduous in autumn ; flowers in panicled 
racemes ; leaves sour, with long bristles on the 
midrib beneath. Oxydendrum. (23). 

a. Leaves evergreen coriaceous, b. 

b. Corolla somewhat irregular, campanulate, without 

little sacs. Rhododendron. (21). 
b. Corolla regular, saucer-shaped. 10-saccate, the an- 
thers at first held in the little sacs. Kalmia. (22). 
41. Choripetalous plants in which the petals arc sometimes 
partly or completely united. 



TRii:i-:s OF the Northern United States 


45 


a. Ovulary 1-locular (1 carpel) with 1 parietal placenta. 
Fabaceae. 

See 15 above. 

a. Ovulary 4-8-locular, with 1 or 2 ovules in each cavity. 
Ilicaceae. 

See 23 above. 

42. Stamens as many as the lobes of the small white corolla ; 
leaves entire, simple and alternate ; with thorns. Sapo- 
TACEAE. 

a. Bumelia. (24). 

42. Stamens twice as many as the lobes of the greenish- 

yellow corolla or more; styles 2-8; plants mostly 
monecious or diccious ; leaves alternate, simple, and 
entire. Ebknaceae. 

a. Diospyros. (25). 

43. Flowers regular, stamens usually 2. Oleaceae. 

a. Chionanthus. (28). 

43. Flowers irregular, zygomorphic ; seeds numerous, stamens 

2-4, didynamous. IFgnoniaceae. 
a. Fith with cavities; stamens 4. Paulownia. (31). 
a. Pith solid; stamens 2. Catalpa. (32). 

11. Stamens twice as many as the lobes of the corolla or 
more; leaves alternate and simple. 45. 

44. Stamens as many as the lobes of the corolla; leaves 

opposite or whorled, simple. 40. 

45. Corolla yellow ; stamens in several series. Symplocaceae. 

a. Symplocos. (26). 

45. Corolla white; stamens in one series. Styracaceae. 
a. Halesia. (27). 

40. Stipules present ; flowers in dense heads in our species ; 
usually blackening in drying. Rubiaceae. 

a. Cephalanthus. (82), 

10. Usually without stipules; flowers in compound cymes in 
our species; not blackening in drying. Caprifoliaceae. 


a. Viburnum. (83). 



CLASSIFICATION AND DESCRIPTION OF THE 
SPECIES. 


SPERMATOPHYTA. SEED-PLANTS. 

Phylum, CYCADOPHYTA. 

Class, Ginkgoae. 

Order, Ginkgoales. 

Ginkgoaceae. Ginkgo Family. 

1. Gmkgo Kaempf Ginkgo. 

Trees with dichotomously veined, fan-shaped leaves on 
thick, wart-like, persistent, dwarf branches. 

Without cones. Stamens and carpels in clusters on the 
dwarf branches, appearing with the leaves. 

1. Ginkgo biloha, L. Maiden-hair-trce. A large beau- 
tiful and hardy diecious tree. Seed large, drupe-like. Autumn 
leaves orange. Introduced from China and Japan; should be 
commonly cultivated for ornament. 

Phylum, STROBILOPHYTA. 

Class, CoNiFERAE. Conifers. 

Order, Finales. 

Taxodiaceac. Bald-cypress Family. 

2. Taxodium Rich. Bald-cypress. 

Trees with feather-like, annually deciduous (ours) dwarf 
branches with the numerous, small, narrow leaves sometimes 
spreading into two ranks or closely oppressed, and having the 
slender twigs covered with small self -pruning scars 

Tall trees with horizontal or drooping branches ; mone- 
cious ; carpellate cones globose, in small terminal clusters ; their 
scales few, each with two ovules at the base. 

1. Leaves on dwarf branches linear, spreading into 2 
ranks. T. distichum. 

1. Leaves on dwarf branches awl-shaped, short, closely ap- 
pressed. T, asccndens. 


( 46 ) 



Trees of the Northern United States 


47 


1. Taxodium distichum (L) Rich. Bald-cypress. A 
large tree, the old bark flaky in thin strips. The roots develop 
upright conic “knees.” Wood light, soft, brown and very 
durable. In swamps and along rivers. N. J. to Fla., west 
to Tex., north to Mo. and Ind. 

2. Taxodium ascendens Brong. Pond-cypress. A 
large tree similar to the preceding, with a greatly enlarged, 
conoidal, broadly ridged base but with fewer “knees.” Wood 
heavier and stronger than in the Bald-cypress In ponds and 
swamps. Southern Va. to Fla. and La. 

Pinaccae. Pine Family. 

Picea I .ink. Spruce. 

Evergreen trees with 4-angled leaves, all of about the same 
length, having the twigs covered with sterigma-bearing scales 
representing leaf bases. 

Conical trees with leaves spirally arranged and spreading 
in all directions ; monecious ; staminate and carpellate cones 
often highly-colored ; carpellate cones pendulous. 

1. Twigs and sterigmata glabrous; carpellate cones cylin- 
dric. 2. 

1. Twigs pubescent, brown; cari>ellate cones ovoid or oval. 

3. 

2. Leaves usually f-1 in. long; carpellate cones 2^-6 in. 

ling. P. abies. 

2. Leaves usually not much over i in. long; very glau- 

cous ; carpellate cones f-2 in. long. P. glauca. 

3. Leaves not glaucous ; cones deciduous at the end of the 

first season. P. rubra. 

3. Leaves glaucous ; cones persistent for two or more 
seasons. P. mariana. 

1. Picea abies (L) Karst. Norway Spruce. A large tree, 
conical in shape when young, with numerous stout spreading 
and drooping branches. Amundant in cultivation. Source of 
Burgundy pitch. Native of Europe. 

2.. Picea glauca (Moench) Voss. White Spruce. 

(P. canadensis (Mill.) B. S. P.) A slender tree sometimes 
with a strong skunk-like odor. Leaves light green, slender, 
4-1 in. long, very acute. An important timber tree with light, 



48 


Field Manual 


soft, weak, and straight-grained wood. Newf. to Alaska, south 
to Me., Mich., and S. Dak. 

3. Picea rubra (DuRoi) Deitr. Red Spruce. A 
slender tree with spreading branches, and slender, sparingly 
pubescent twigs. Wood soft, weak and pale reddish. Newf. 
to northern N. Y. and Minn.; along the Alleghenies to Va. and 
Ga. 

4. Picea mariana (Mill.) B. S. P. Black Spruce. A 
tree with spreading branches and smooth or only slightly 
roughened bark. Leaves not over in. long, stout, green, 
closely covering the twigs. Wood light and straight-grained; 
used for paper pulp, for general lumber and for masts and 
spars of ships. Newf. to N. W. Terr., south to N. J., N. C., 
Mich, and Minn. 

4. Tsuga Carr. Hemlock. 

Evergreen trees with flat linear leaves, those on the top 
of the twig short, and having the twigs covered with sterigma- 
bearing scales representing leaf bases. 

Branches slender, horizontal or drooping ; leaves spreading 
more of less into 2 ranks; monecious ; carpellate cones small, 
pendulous. 

1. Tsuga canadensis (L.) Carr. Hemlock. A tall tree 
with slender, horizontal or drooping branches, the old bark 
flaky in scales. Wood very coarse, light, brittle, and soft: 
used for wood pulp. Bark used for tanning. Source of 
Canada pitch. Self-prunes twigs. N. S. to Minn, south to 
Ohio, and Del., along the Alleghanies to Ala., and to Mich, 
and Wis. 

5. Abies (Tourn.) Hill. Fir. 

Evergreen trees with fiat linear leaves, rarely prismatic, 
without sterigma-bearing scales, but with prominent circular 
leaf scars with a central bundle scar. 

Carpellate cones erect, the scales deciduous; monecious; 
carpellate bract longer or shorter than the ovuliferous scale. 

1. Carpellate bract aristate, longer than the ovuliferous 
scale; leaves mostly emarginate. A. fraseru 

1. Carpellate bract serrulate, shorter than the ovuliferous 
scale or but little longer; leaves obtuse. A. balsamea. 



Trkks of the Northern United States 


49 


1. Abies fraseri (Pursh) Poir. Fraser Fir. A slender 
tree growing on the high Alleghanies. Bark smooth, with 
resin blisters. W. Va., N. Car., and Tenn. 

2. Abies balsamea (L.) Mill. Balsam Fir. A slender 
short-lived tree with smooth blistered bark. Wood very light 
and soft. Canada balsam is obtained from its resin, Newf. 
to Hudson Bay and Alberta, south to Penn., along the Alle- 
ghanies to Va., and to Mich., Iowa, and Minn. 

6. Larix (Tourn.) Adans. Larch. 

Trees with thick wart-like dwarf branches bearing a clus- 
ter of deciduous needle-shaped leaves. 

Tall pyramidal, monecious trees with horizontal or ascend- 
ing branches ; carpellate cones small, erect, with thin woody 
scales. 

1. Carpellate cones small, i-l in. long, oval or almost 
globular; ovulifcrous scales glabrous; native, grow- 
in bogs and wet places. L. laricina. 

1. Carpellate cones rather large 1-1 J in. long; ovuliferous 
scales finely tomentose on the back, cultivated in dry 
ground. L. decidua. 

1, Larix laricina (DuRoi) Koch. Tamarack. A slen- 
der tree with close or at length scaly bark. Wood hard, dur- 
able, and very strong ; used in ship-building, for railroad ties, 
posts, and telegraph poles. In swamps and about the margins 
of lakes. Newf. to N. W. Terr., south to Minn., Ind., Ohio, 
and N. J. 

2. Larix decidua Mill. European Larch. A beautiful tree 
with horizontal branches and drooping branchlets, conical in 
shape when young ; much cultivated in some parts of the United 
States. The source of Venice turpentine. Native of Europe. 

7. Pinus (Tourn.) L. Pine. 

Evergreen trees with self-pruned dwarf branches bearing 
1-7 needle-shaped leaves. 

Resinous, monecious trees with very small dwarf branches ; 
dwarf branches and ordinary twigs covered with scale leaves. 
Dwarf branches self-pruned after a number of years. Car- 
pellate cones woody with numerous carpels. Our most im- 
portant lumber trees. 



50 


Field Manual 


1. Dwarf branches with 5 foliage leaves ; ovuliferous 
scales little thickened at the tip. P. strohus. 

1. Dwarf branches with 2-3 foliage leaves ; ovuliferous 

scales much thickened at the tip. 2. 

2. Dwarf branches with 3 foliage leaves, rarely 2 or 4. 3. 

2. Dwarf branches mostly with 2 foliage leaves ; some of 

them may be with 3. 5. 

3. Leaves G-10 in. long; carpellate cone oblong-conic or 

ovoid. 4. 

3. Leaves 3-5 in. long; carpellate cones ovoid. P. rigida. 

4. Old sheaths of the dwarf branches i-1 in. long; leaves 

not glaucous ; carpellate cones oblong-conic. P. iaeda. 

4. Old sheaths about h in. long; leaves glaucous; carpel- 

late cones ovoid. P. seroHna. 

5. Twigs glaucous; resin-ducts parenchymatous; carpellate 

cones H-3 in. long; ovuliferous scales with a prickle 
or small spine. 6. 

5. Twigs not glaucous. 7. 

6. Leaves slender, 21-5 in. long; buds not very resinous; 

prickles of the ovuliferous scales short and small. P. 
echinata, 

6. Leaves stout, H-2i in. long; buds very resinous; 

prickles of the ovuliferous scales long and stout. P. 
virginiam. 

7. Leaves 1-4 in. long, grayish-green or light green; ovu- 

liferous scales without or with a small prickle, or 
with a thick point or spine. 9. 

7. Leaves 4-6 in. long, dark-green; ovuliferous scale with- 

out a spine or prickle, or sometimes with a very 
small prickle. 8. 

8. Foliage lustrous, resin ducts peripheral; carpellate 

cones terminal or subterminal, oval-conic; ovulifer- 
ous scales pointless when mature. P. resinosa. 

8. Foliage dull ; resin ducts parenchymatous ; carpellate 

cones lateral, ovoid-conic; ovuliferous scale with a 
small prickle. P, nigra, 

9. Leaves 2i-4 in. long, grayish-green; twigs orange or 

brown; resin ducts parenchymatous; carpellate cones 
ovoid ; 3-5 in. long. P. pungens. 

9. Leaves in. long. 10. 



Trees of the Northern United States 


51 


10. Leaves in. long, grayish-green; twigs dull green- 

ish-yellow or greenish-brown ; resin ducts peripheral ; 
carpellate cones ovate-conic, 2-3 in. long. P. silvestris. 

10. Leaves i-U in. long; resin ducts parenchymatous; car- 
pellate cones oblong-conic 1-2 in. long, usually up- 
wardly curved. P. banksiana. 

1. Pinus strobus L. White Pine. A large tree with 
nearly smooth bark, except when old; branches horizontal in 
whorls. Often forming dense forests. Wood soft and straight- 
grained ; used in enormous quantities for building purposes. 
One of the most valuable timber trees in the world. Has been 
more extensively used in America for lumber than any other 
tree. Newf. to Man., south along the Allegh. to Ga. and to 
Ohio, 111. and Iowa. 

2. Pinus resinosa Ait. Red Pine. A tall tree with 
reddish bark. Wood rather hard but not very durable. Tur- 
pentine is obtained to a limited extent from this species. A 
tree of rapid growth. Newf. to Man., Mass., Penn., and Minn. 

3. Finns nigra Arn. Austrian Pine. A tall open, pyra- 
midal tree of rapid growth with the thick spreading branches 
in regular whorls. Often cultivated. From Europe. 

4. Pinus stives' tris L. Scotch Pine. A large and valuable 
tree with drooping branches; much cultivated. From it are 
obtained the red and yellow deal much used as lumber in 
Europe. Native of northern Europe. 

5. Pinus taeda L. Loblolly Pine. A large tree of very 
rapid growth with spreading branches and thick, rugged bark, 
flaky in age. Wood rather hard; much used for lumber in 
the South. Often growing in old fields. N. J. to Fla., Ark., 
and Texas. 

6. Pinus serotina Mx. Pond Pine. A tree usually with 
a short trunk and with the bark fissured into small plates. 
In swamps and ponds. Wood soft, brittle, and coarse-grained. 
Coastal plain. N. J. to Fla. 

7. Pinus rigida Mill. Pitch Pine. A tree with spread- 
ing branches, the old bark rough and furrowed, flaky in 
strips. Sprouts readily from the stump if cut down or burned. 
Wood rather hard and brittle and full of resin; used for fuel, 



52 


Field Manual 


charcoal, and coarse lumber. A source of turpentine to a 
limited extent. In dry, sandy or rocky soil. N. B. to Out., 
Tenn., Ohio, W. Va. and (ia. 

8. Pinus banksiana Lamb. Jack Fine. A slender tree 
with spreading branches, tlie bark becoming flaky. Wood light 
and rather soft. In sandy soil. N. B. and N. W. Terr., 
south to Me., N. Y., 111., and Minn. 

9. Pinus echinata Mill. Shortlcaf Yellow Fine. A 
large tree wnth spreading branches ; leaves sometimes in 3’s, 
sometimes in 2’s. Wood rather hard and very valuable ; much 
u.sed as lumber. Also furnishes some turpentine. Produces 
shoots from stumps. In sandy soil. N. Y. to Fla., Ohio, III., 
Okla., and Texas. 

10. Pinus pungens Lamb. Table-mountain Pine. A 
tree with spreading branches, the old bark rough and in 
flakes; leaves sometimes in -Vs. Wood light and soft; much 
used for charcoal. N. J. to Ga. and Tenn. 

11. Pinus virginiana Mill. Scrub Pine, A slender, 
usually small tree with spreading or drooping branches ; the old 
bark flaky and dark-colored. Wood very resinous, soft and 
durable but of poor quality. In sandy soil. L. I. to S. C., 
Ala., Tenn., Ohio, and Ind. 

Jiinipcraccac. Junii>er Family. 

Subfamily, Cupressatae. 

8. Thuja L. Arborvitae. 

Evergreen trees or shrubs with decidedly flattened and 
fan-like twigs, and with naked buds, the small leaves opposite, 
scale-like, appressed and 4-ranked; carpellate cone oblong, with 
6-10 scales, the 4 upper fertile. 

Resinous and aromatic; flowers minute, monecious ; ovules 
usually 2 on each scale, erect ; scales dry coriaceous, not peltate. 

1. Branchlets spreading more or less horizontally with 
a distinct upper and lower side ; carpellate cones 
pendulous, the thin scales appendiculate below the 
apex ; seeds winged. T. occidentalis, 

1. Branchlets in a vertical plane with both sides alike; 
carpellate cones erect, the scales with a prominent 



Treks of the Northern United States 


58 


horn-like process below the apex ; seeds wingless. 
7'. orientalis. 

1. Thuja occidentalis L. American Arborvitae. Us- 
ually a small conical tree with fan-like branches. Self-prunes 
twigs. Wood light and durable; used for posts, railroad ties, 
etc. Usually in wet soil and along the banks of streams. 
N. F. to Man., south to Ohio and N. J., along the Alleghanies 
to N. C., and to 111. and Minn. 

2. Thuja orientalis L. Chinese Arborvitae. A small pyra- 
midal or bushy tree with spreading and ascending branches. 
Native of Asia. Cultivated in many forms. Probably better 
regarded as belonging to a distinct genus, Biota Endl. — B. ori- 
cntalis (L.) Endl. 

9. Libocedrus Endl. Incense-cedar. 

Evergreen trees with naked buds and small, scale-like, 
appressed, opposite, 4-ranked, usually long decurrent leaves on 
somewhat flattened branches; scales of the carpellate cone 4-G, 
the two middle ones fertile, not peltate. 

Tall, resinous aromatic trees with scaly bark, monecious; 
staminate and carpellate cones on separate branchlets ; seeds 
with unequal lateral wings. 

1. Libocedrus decurrens Torr. Incense-cedar. A tree 
with a tall, straight slightly lobed trunk, tapering from a 
broad base. Wood light, soft, close-grained, and very durable 
in contact with the soil. From the Pacific coast ; often culti- 
vated as an ornamental tree. 

10. Chamaecyparis Spach. White-cedar 

Evergreen trees with small, scale-like appressed, nearly or 
quite similar leaves, naked buds, and dry peltate carpellate 
scales with 2-4 seeds. 

Monecious ; carpellate cones globose, with thick, opposite 
scales, each with a central^*^int. 

1. Leaves dull blue-green; bark thin, divided into flat 
ridges. C. thyoides. 

1. Leaves bright green; bark thick, divided into broad 
ridges. C. lawsoniana. 



54 


Field Manual 


1. Chamaecyparis thyoides (L.) B. S. P. Southern 
White-cedar. A tree with soft, light, and durable wood ; used 
for boat-building, woodenware, shingles, etc. In swamps. 
Maine to N. H., N. J., Fla., and Miss. 

2. Chamaecyparis laivsoniana (Murr.) Pari. Lawson Cy- 
press. A large tree with an abruptly enlarged base and a 
spire-like crown of small horizontal or pendulous branches. 
Bark often 10 in. thick. Wood light, hard, and strong, 
abounding in fragrant resin. From the Pacific coast. Many 
varieties in cultivation. 

Subfamily, Juniperatae. 

11. Jumperus L. Juniper. 

Evergreen trees or shrubs with naked buds, subulate or 
scale-like leaves, one or both kinds on a tree, and with car- 
pellate cones developing into a bluish-black berry-like fruit. 

Carpcllate cones small, globose ; plants usually deicious, 
sometimes monecious, pungent aromatic; bark usually thin and 
shreddy. 

1. Leaves all subulate, prickly pointed, verticillate, slender, 
mostly straight; cones axillary. /. communis. 

1. Leaves of 2 kinds, scale-like and subulate, opposite or 
verticillate ; cones terminal. /. virginiana. 

1. Juniperus communis L. Common Juniper. A low 
tree with spreading or drooping branches and shreddy bark. 
Goats are poisoned from eating the leaves. On dry hills. N. S. 
to Alaska, south to N. J., Ohio, Mich., Neb., and in the Rocky 
Mts. to N. Mex. Also in Europe and Asia. 

2. Juniperus virginiana L. Red Juniper. A tree with 
spreading often irregular branches when old, but conic in 
shape when young. Self-prunes twigs. Wood very valuable, 
light, straight-grained, durable, and fragrant; used for posts, 
cabinet-work, interior finish, veneers, moth-proof chests and 
cooperage, and almost exclusively in the manufacture of lead 
pencils. Often infested with the “cedar apple.” Poisonous 
to goats. In dry soil; common on bluffs. N. B. to western 
Ont. and S. Dak., south to Fla. and Texas. 

Taxus haccata L. European Yew (Order, Taxales; Fam- 
ily, Taxaceae), becoming a large tree is sometimes planted. 



Trees of the Northern United States 


55 


It has fleshy drupe-like red fruits and minute staminale cones 
with peltate stamens, like the shrubbery American Yew, Taxus 
canadensis Marsh. 

Phylum, ANTHOPHYTA. 

Class, Dicotylae. Dicotyls. 

Subclass, Thalamiflorae. 

Order, Ranales. 

Magnoliaccae. Magnolia Family. 

12. Magnolia L. Magnolia. 

Shrubs or trees with alternate, simple, entire leaves, not 
truncate, and with complete stipular rings. 

Bark bitter aromatic ; flowers bisprangiate, large, solitary ; 
buds covered with connate, sheating stipules ; pith usually 
diaphragmed but solid ; fruit aggregate, cone-like. 

1. Leaves acute or rounded at the base. 2. 

1. Leaves auriculate or cordate at the base. 4. 

2. Leaves rounded or truncate at the base, thin. Leaf 

ouds silky pubescent. M. acuminata. 

2. Leaves acute at the base. 3. 

3. Leaves light green beneath, 1-2 ft. long. Leaf buds 

glabrous. M. fripctala. 

3. Leaves glaucous beneath, 3-6 in. long. Leaf buds 

pubescent. M. virginiana. 

4. Leaves auriculate, glabrous. Leaf buds glabrous. M. 

frascri. 

4. Leaves cordate at the base, glaucous-white and pubes- 
cent beneath; leaf buds tomentose. M. macrophylla. 

1. Magnolia acuminata L. Cucumber Magnolia. A 
large tree with silky pubescent leaf-buds. Leaves oval, acute or 
somewhat acuminate, rounded or truncate at the base, i-1 ft. 
long; flowers greenish-yellow. Wood soft, light, and durable; 
used for cabinet-work, pump-logs, and water-troughs. N. Y. 
to Ontario and Mo., Ga., Ala., and Ark. 

2. Magnolia tripetala L. , Umbrella Magnolia.. A low 
tree with glabrous leaf-buds and irregular branches. Leaves 
obovate, acute, cuneate at the base, 1-2 ft. long, flowers white, 
slightly odorous. Wood soft and light. Penn, to Ga., Mo., 
Ark., and Miss. 



56 


Field Manual 


3. Magnolia virginiana L. Laurel Magnolia. A tree 
with pubescent leaf-buds. Leaves oval or oblong, acute at the 
base, 3-6 in. long ; flowers white, deliciously fragrant. In 
swamps. Mass, to Penn., Fla., Ark., and Texas. 

4. Magnolia fraseri Walt. Fraser Magnolia. A tree 
with spreading branches and glabrous leaf buds. Leaves elon- 
gated-obovate or oblong, auriculate, L2 ft. long ; flowers white. 
In mountain woods. Va. and Ky. to Fla. and Miss. 

5. Magnolia macrophylla Mx. Large-leaf Magnolia. 
A tree, sometimes branching near the base, with very large 
leaves, 1-3^ ft. long, and pubescent twigs. Flowers large, LI 
ft. in diameter, fragrant, white with a purple center; fruiting 
cone broadly oval, bright rose-colored at maturity. Pleart- 
wood brown satiny, hard ; sap-wood light yellow, in woods ; 
southern Ohio to N. Car., Fla., Ark., and La. 

Various Magnolias are in cultivation, the more common one 
is Magnolia soulangiana Soul. Soulange’s Mgnolia, a small 
tree with large purplish-pink flowers appearing before the 
leaves. 

13. Liriodendron L. Tuliptree. 

Trees with alternate, truncate, simple leaves, with solid, 
diaphragmed pith and complete stipular rings. 

Buds with connate stipules; flowers large, perianth trimer- 
ous ; anthers linear, extrorse ; fruit aggregate, cone-like, dry. 

1. Liriodendron tulipifera L. Tuliptree. A very large 
magnificent, rapid-growing tree with glabrous leaf-buds. Flow- 
ers greenish-yellow, orange-colored within. Autumn leaves pure 
yellow. Next to the Sycamore, probably the largest tree in 
the Northeastern United States; trunk sometimes 34 feet in 
circumference. Wood light, soft, and straightgrained, easily 
worked ; heart wood light yellow or brown ; sapwood thin, 
nearly white. Used for interior finish, shingles, boat-building, 
panels of carriages, wooden pumps, wooden ware of various 
kinds, wood pulp, furniture, implements, boxes, shelving, draw- 
ers, and for carving and toys. One of the best woods for 
paneling. Should be extensively cultivated. Vt. and R. L 
to Fla., Mich, Ark., and Miss. 



Trees of the Northern United States 


57 


Anonaccae. Custard-apple Family. 

14. Asimina Adans. Papaw. 

Trees or shrubs with alternate, 2-ranked, simple, entire, 
pinnately veined, deciduous leaves and diaphraged, solid pith. 

Buds naked, silky ; bark with fetid odor ; perianth trimer- 
ous; carpels 3-15. 

1. Asimina triloba (L.) Dunal. Papaw. A small tree 
or shrub with smooth dark bark and nodding young twigs. 
Flowers axillary, nodding; fruit a large, fleshy, oblong, green- 
ish-yellow, edible berry, which, however, does not agree with 
some persons. A case of severe poisoning from eating the 
fruit is recorded. In creek and river bottoms and on hillsides. 
Out. and N. Y. to Mich., Neb., Tex., and Fla. 

Lauraceae. Laurel Family. 

15. Persea (Plum.) Gaertn. Bay. 

Aromatic, evergreen trees or shrubs with alternate, simple, 
pinnately veined, entire leaves. 

Perianth 6-parted; stamens and staminodes 12, in 4 series; 
fruit a globose or oblong berry. 

1. Persea borbonia (L.) Spreng. Red Bay. A tree 
with red bark and lanceolate or oblong-lanceolate, puberulent 
or nearly glabrous leaves. Wocxl hard, strong, bright red in 
color, and rather brittle; used for cabinet-making and interior 
finish. Along streams and the border of swamps. Del. to Fla., 
Ark., and Texas. 

16. Sassafras Nees and Eberm. Sassafras. 

Trees with entire or 3-lobed, alternate leaves with 2 prom- 
inent lateral veins, with spicy aromatic bark and unequal inter- 
nodes. 

Flowers diecious; perianth 6-parted; fruit a blue drupe. 

1. Sassafras variifolium (Salisb.) Ktz. Sassafras. A 
large rough-barked tree, the sap of the bark and leaves muci- 
laginous. Autumn leaves red, yellow, and green. Wood red- 
dish, light and rather soft, of coarse texture, durable; used in 
cooperage, for small boats, and fencing. The bark of the roots 
yields a powerful, aromatic stimulant. Fruit pungent, poison- 



58 


Field Manual 


ous. Excessive doses of Sassafras tea produce narcotc poison- 
ing. In dry or sandy soil. Me. to Ont., Mich., Iowa, Fla., 
and Texas. 

Order, Geraniales. 

Ruiaceae. Rue Family. 

17. Zanthoxylum L. Prickly-asli. 

Trees or shrubs with alternate, piniiately compound, punc- 
tate leaves and with stipular spines. 

Bark acrid aromatic; flowers imperfectly diecious; fruit a 
capsule with 1-2 seeds. 

1. Zanthoxylum americanum Mill. Prickly-ash. A 
prickly shrub or small tree with small flowers in sessile axillary 
cymes ; stamens 3-5 ; carpels 2-5 distinct, seed oblong black and 
shining. Wood soft and light brown. In woods and thickets. 
Quebec to Va., Ontario, S. Dak., and Kan. 

18. Ptelea L. Hoptree. 

Shrubs or small trees with alternate, trifoliate, punctate 
leaves and superposed buds covered by the petiole base. 

Bark bitter; flowers imperfectly monosporangiate ; stamens 
4-5; fruit a samara with a membranous wing; ovulary 2-loc- 
ular. 

1.. Ptelea trifoliata L. Hoptree. A shrub or small 
tree with sunken superposed axillary buds covered by the petiole 
base. Bark and flowers with a disagreeable odor. Wood light 
brown, heavy, and hard. In woods. Conn, to Fla., Ont., Minn., 
Kan., and Mexico, 

Simarubaceac. Ailanthus Family. 

19. Ailanthus Desf. Ailanthus. 

Large trees with alternate, pinnately compound, large leaves 
having green glands on the under side of the teeth at the base 
of the leaflets. 

Branches robust with large brown pith ; flowers diecious ; 
the 5 samaras linear or oblong, usually twisted. 

1. Ailanthus altissima (Mill.) Swingle. Tree-of- 
heaven. A large tree of rapid growth with thick branches and 
smooth bark. Leaves ill-scented; leaflets with green glands 



Trees of the Northern United States 


59 


under the lobes or teeth. Autumn leaves pure yellow. Wood 
hard and useful. Sprouts freely from the roots and is easily 
propagated from root cuttings. A pest in pastures in some 
states; cows will not eat grass near the young shoots. Water 
contaminated by the leaves is poisonous. Naturalized from 
China. Ont. to Mass., Va., and Kan. 

Order, Malvales. 

Tiliaccae. Linden Family. 

20. Tilia (Tourn.) L.. Linden. 

Trees with 2-ranked, simple palmately veined, inequilateral, 
serrate or dentate leaves and solid pith. 

Flowers bisporangiate, pentamerous, stamens numerous ; 
dry drupaceous fruit in cymose clusters, the peduncle subtended 
by a broad membranous bract. 

1. Leaves glabrous or nearly so on both sides at maturity, 
except on the veins and in their axils. 2'. 

1. Leaves pubescent beneath at maturity. 3. 

2. Petals with scales at the base; inflorescence without 

bracts ; leaves comparatively large ; native. T. amer- 
icana, 

2. Petals without scales at the base, inflorescence with 

large bracts; leaves comparatively small; cultivated. 
T. europaea. 

3. Leaf blades with white, gray, or silvery-gray pubescence 

beneath or sometimes brownish in T. heterophylla. 4. 

3. Leaf blades with brown or rusty pubescence beneath, 

smooth and shining above. T. ncglecia. 

4. Peduncle bracts mostly abruptly narrowed to the base 

of the peduncle ; leaf blades ovate, gray or silvery 
beneath; obliquely truncate or slightly cordate at the 
base. T. heterophylla, 

4. Peduncle bracts mostly gradually narrowed to the 
peduncle above the base; leaf blades longer and nar- 
rower than in the preceding species and obliquely 
cordate at the base. T, michauxii, 

1. Tilia americ^na L. American Linden. Inch 
T. glabra Vent. A large straight-trunked tree with spreading 



(JO Field Manual 

branches. Inner bark very tough; used for mats and coarse 
rope. Wood soft and very white, light and uniform in texture, 
not liable to crack ; called “basswood’' ; used for wooden-ware, 
cabinet-work, trunks, paneling of carriages, in cooperage, and 
for toys. The bark and wood of the other lindens are much 
the same. In rich soil, on bluffs, and along river bottoms. 
N. B. to Va., Manitoba, Kan., and Texas. 

2. Tilia curopaca L. European Linden. A large tree 
much cultivated in various varieties in parks. Its name, Lin, 
was the origin of the family name of Linnaeus. 

3.. Tilia neglecta Spach. Rusty-leaf Linden. A tall 
tree with furrowed and scaly, reddish-brown bark. Twigs 
glabrous ; leaves acute or abruptly acuminate, smooth and shin- 
ing above, covered below with short persistent pubescence and 
with conspicuous axilary tufts. Wood as in T. amcricana. 
In rich moist ground. Que., Mass., and N. Y. to N. Car., and 
Miss. 

4. Tilia heterophylla Vent. White Linden. A large 
tree with slender, glabrous twigs and with large ovate leaves, 
gray or silvery-gray beneath and with an obliquely truncate 
or slightly cordate base. Wood much as in the preceding. N. Y. 
to Fla., Ala., Ky., W. Va., and Ind. 

5. Tilia michauxii Nutt. Michaux’s Linden. A large 
tree with elongate-ovate leaves obliquely cordate at the base, 
the vein axils usually without axillary tufts. Wood with the 
same general characteristics as the other lindens. In rich soil. 
Conn, to Ind., Ga., Miss., Ark., Mo., and 111. 

Subclass, Heteromerae. 

Order, Ericales. 

Ericaceae, Heath Family. 

21. Rhododendron L. Rhododendron. 

Shrubs or small trees with simple, alternate, entire, pin- 
nately veined, coriaceous, evergreen leaves and very scaly 
winter buds. 

Flowers showy, bisporangiate, pentamerous, sympetalous; 
fruit usually a woody capsule with numerous seeds. 

1. Rhododendron miximum L. Great Rhododendron. 



Trees of the Northern United States 


G1 


A tall shrub or small tree with beautiful flowers and striking 
evergreen leaves. Leaves poisonous to stock and the nectar 
said to produce poisonous honey. On rocky hillsides and along 
streams. Occasionally cultivated. N. S. to Ont., Ohio, Ga., 
and Ala. 

22. Kilmia L. Kalmia. 

Shrubs or small trees with simple, alternate, entire, pin- 
nately veined, coriaceous evergreen leaves, and with naked 
winter buds. 

Flowers bisporangiate, pentamerous, sympetalous ; stamens 
10, the anthers at first in 10 pouches; fruit a capsule with small 
seeds. 

1. Kalmia latifolia L. Mountain Kalmia. A shrub 
or small tree with evergreen leaves. All parts of the plant 
poisonous to cattle, sheep, and other animals. The honey from 
the flowers is said to be poisonous ; also the flesh of game 
that has fed upon the leaves or fruit. In woods and on rocky 
hillsides. Occasionally planted. N. B. to Ont., Ohio, Ind., 
Pda., and La. 

23. Oxydendrum DC. Sorrcl-tree. 

Trees with simple alternate, pinnatcly veined, serrate, sour 
leaves, not glandular, but with prominent scattered bristle-like 
hairs on the midrib beneath; and with cylindrical pith and a 
central ring-shai>ed bundle-scar. 

Flowers bisporangiate, pentamerous, white, numerous in 
terminal panicled racemes ; fruit a capsule. 

1. Oxydendrum arboreum (L.) DC. Sorrel-tree. A 
small tree with smooth bark and brilliantly red-colored leaves 
in autumn. Wood hard and close-grained, reddish-brown; used 
for handles of tools, bearings of machinery, etc. On hillsides. 
Ind., Ohio and Penn, to Va., Fla., and Ala. 

Order, Ebenales. 

Sapotaceae. Sapodilla Family. 

24. Bumelia Sw. Bumclia. 

Shrubs or small trees with alternate, simple, pinnately 
veined, entire leaves; with milky sap; and usually with both 
terminal and axillary thorns. 



62 


Fielj) Manual 


Flowers small in axillary fascicles, pentamerous ; fruit a 
fleshy berry with a single seed. 

1. Leaves glabrous or nearly so; oblanceolate to oblong- 
ovate, 2-5 in. long. B. lycioides. 

1. Leaves tomcntose or silky; oblong-obovate to cuneate- 
obovate, usually obtuse, 1-3 in. long. B. lanuginosa. 

1. Bumelia lycioides (L.) Gacrtn. f. Buckthorn Bu- 
melia. A shrub or small tree usually with thorns and thornlike 
spurs and with gray bark. Leaves tardily deciduous. Wood 
very hard, yellowish-brown. In moist soil. Va. to 111., Mo., 
Fla., and Texas. 

2. Bumelia lanuginosa (Mx.) Pers. Woolly Bumelia. 
A shrub or rather large tree with persistent leaves. Wood 
rather soft, weak, yellowish-brown. III. to Kan., Tex., Ga., 
and Fla. 

Ehenaccae. Ebony Family. 

25. Diospyros L. Persimmon. 

Trees, ours with alternate, pinnately veined, entire, de- 
ciduous leaves, having the petiole jointed to the twig ; and 
with a central bundle scar. 

Flowers monosporangiate ; fruit a large berry with 4-12 
flat oblong seeds. 

1. Diospyros virginiana L. Persimmon. A hand- 
some tree with hard, dark, furrowed bark. Pith often with 
cavities. Berry large, pulpy, yellow, exceedingly astringent 
when green, but sweet and edible after frost. Bark astringent 
and tonic. Wood very hard, heavy, strong, and tough, close- 
grained and dark-colored; used in turnery, for shuttles, plane 
stocks, and shoe lasts. R. I. to Ohio, Iowa and Kan., Fla., 
and Texas. 

Symplocaceae. Sweetleaf Family. 

26. S:^mplocos Jacq. Sweetleaf. 

Shrubs or trees with simple, alternate, serrate or repand 
leaves; with diaphragmed pith showing lenticular cavities; and 
with axillary buds not superposed. 

Flowers bisporangiate, pentamerous, but the stamens nu- 
merous; fruit a small, mostly nearly dry drupe. 



Trees of the Northern United States G3 

1. Symplocos tinctoria (L.) L'Her. Sweetleaf. A 
shrub or small tree, the pith diaphragem. Flowers bright yel- 
low, fragrant; drupe nutlike. Wood soft, weak, pale red or 
white. Del. to Fla., La., and Ark. 

Styracaceae, Storax Family. 

27. Halesia Ell. Silverbell. 

Shrubs or small trees with simple, alternate, serrate leaves, 
with diaphragmed pith showing cavities ; and with superposed 
axillary buds. 

More or less stellate pubescent ; flowers large, white, droop- 
ing, in lateral fascicles or short racemes ; fruit dry, 2-4-winged. 

1. Halesia Carolina L. Silverbell. A small tree with 
diaphragmed pith. Wood soft, light brown. In woods and 
along streams. Va. to 111., Fla., and Ala. 

Subclass, Tubiflorae. 

Order, Gentianales. 

Olcaceae. Olive Family. 

28. Chionanthus L. Fringctree. 

Shrubs or small trees with opposite, simple, entire decidu- 
ous leaves, pinnately veined to the tip ; and with pubescent 
twigs and buds. 

Flowers bisporangiate, in large loose panicles ; perianth 
tetramerous ; fruit a drupe. 

1. Chionanthus virgmica L. Fringetree. A shrub or 
small tree with handsome, white, fragrant flowers in drooping 
panicles. Wood heavy, hard, and light brown. In moist soil. 
N. J. and Ohio to Fla., Mo., and Texas. 

29. Forestiera Poir. Adelia. 

Shrubs or small trees with simple, opposite, pinnately 
veined, usually serrate leaves ; with brown twigs ; and usually 
with thorns and superposed buds. 

Flowers diecious or imperfectly monosporangiate, in fas- 
cicles, or paniculate, from scaly buds; fruit a drupe. 

1. Forestiera acuminata (Mx.) Poir. Adelia. A 
shrub or small tree usually with somewhat thorny branches. 



CA 


Field Manual 


Wood heavy, soft, yellowish-brown, not strong. On river 
banks. Ind. to Ga., Mo., Ark., and Texas. 

30. Fraxinus (Tourn.) L. Ash. 

Trees with opposite odd-pinnate leaves without stipules or 
stipels and with closely crowded bundle scars in a curved line. 

Flowers sympetalous or apetalous, bisporangiate or mono- 
sporangiatc ; stamens usually 2 ; fruit a samara. 

1. Leaflets sessile. 2. 

1. Leaflets more or less stalked. 8. 

2. Leaflets 7-11, long, gradually tapering to a point, 

oblong lanceolate. F. nigra. 

2. Leaflets short pointed, ovate to obovatc. F. excelsior. 

3. Twigs not quadrangular. 4. 

3. Twigs quadrangular; stems sometimes sharply four- 

angled; leaflets 7-11, green on both sides, upper ones 
usually sessile, lower ones short stalked. F. quad- 
rangulata. 

4. Twigs pubescent, often velvety. 5. 

4. Twdgs smooth or nearly so. 7. 

5. Leaflets ovate to ovate lanceolate ; base usually trun- 

cate or rounded, unsymmetrical ; upper surface dark 
yellow-green, soft pubescent beneath ; calyx large. 
F. profunda. 

0 . Leaflets ovate, ovate-lanceolate, or lanceolate, usually 
acute at the base ; calyx minute. 6. 

6. Leaflets pale beneath; ovate to ovate-lanceolate, 7-11; 

wing of samara terminal or nearly so. F. hiltmoreana. 

6. Leaflets green or greertish beneath, ovate-lanceolate to 

lanceolate, 5-9 ; samara with a decurrent wing. F. 
pennsylvanica. 

7. Leaflets pale beneath, ovate to ovate-lanceolate, entire 

or indefinitely serrate, abruptly acute or acuminate, 
glabrous or somewhat pubescent ; wing of samara 
terminal. F. americana. 

7. Leaflets green on both sides, glabrous or somewhat 
pubescent, usually serrate, lanceolate to ovate-lanceo- 
late, acuminate ; wing of samara decurrent on the 
sides of the slender body. F. Icmceolata. 



Trees of the Northern United Staitss Gd 

1. Fraxinus quadrangulata Mx. Blue Ash. A large 
tree with 4-sided or 4- winged twigs. Leaflets 7-11, ovate, 
oblong, or lanceolate, acuminate, green on both sides, sharply 
serrate or serrulate; samara linear-oblong or cuneate, winged 
all around, parallel-nerved, the body extending more than half- 
way to the apex. The inner bark furnishes a blue dye. Wood 
heavy, hard and valuable ; used for flooring, carriage-making, 
etc. Ont., Minn., and Mich., to Ala., Iowa and Ark. 

2. Fraxinus nigra Marsh. Black Ash. A large tree. 
Leaflets 7-11 glabrous, green on both sides, sessile, oblong- 
lanceolate, long acuminate, sharply serrate or serrulate, samara 
oblong or linear-oblong, parallel-nerved, the body flat, winged 
all around and extending to or beyond the middle. Wood 
heavy, soft, dark brown, used for barrel hoops, baskets, cabinet- 
work and interior finish. In swamps and wet soil. Newf. to 
Man., Va., and Ark. 

3. Fraxinus excelsior L. European Ash. A fine hardy 
tree with bright green leaves. Samara flat, linear-oblong. 
Weeping varieties are in cultivation. Native of Europe. 

4. Fraxinus profunda Bush. Pumpkin Ash. A large 
tree with thick, gray, fissured bark and velvety pubescent twigs. 
Leaflets 7-9, ovate-lanceolate to oblong-lanceolate, stalked, 
acuminate, bright green above, paler and pubescent beneath, 
large. Samara with a flattish body, wing decurrent to below 
the middle. In swamps. Va. to 111., Mo., Ark., and Fla. 

5. Fraxinus pennsylvanica Marsh. Red Ash. A large 
tree with velvety-pubescent twigs. Leaflets 5-9, ovate, ovate- 
lanceolate, or oblong, acuminate or acute, usually denticulate; 
body of the samara linear margined above by the linear or 
spatulate decurrent wing. Wood hard, strong, brown. In moist 
soil. N. B. to Minn., Fla., and Kan. 

6. Fraxinus lanceolata Borkh. Green Ash. A large 
tree with glabrous twigs. Leaflets 5-9, entire or denticulate, 
ovate or oblong-lanceolate, acuminate or acute, green on both 
sides ; samara similar to that of the two preceding species, wing 
usually spatulate and decurrent on the sides of the body below 
the middle. Wood rather inferior in value to that of the white 



60 


Field Manual 


ash. In moist soil, on flood-plains, and on bluffs. Me. to Sask., 
south to Fla., Kan., and Texas. 

7. Fraxinus biltmoreana Bead. Biltmore Ash. A 
tree with the young twigs pubescent. Leaflets 7-9, ovate to 
lanceolate, acuminate, entire or obscurely denticulate, more or 
less pubescent beneath ; body of the samara narrowly elliptic, 
terete; wing linear, or somewhat broadened above, 2-3 times 
the length of the body. Woodlands and river banks. Penn, 
and Ohio to Ga. 

8. Fraxinus americana L. White Ash. A large tree 
of rapid growth, with glabrous twigs. Leaflets 5-9, ovate, ovate- 
lanceolate, oblong, or rarely slightly obovate, entire or den- 
ticulate, pale and often pubescent beneath, acuminate or acute ; 
body of the samara terete, not margined, winged only from 
near the summit, l-h the length of the wing. Autumn leaves 
brown, purple, and salmon. Wood heavy, hard, strong, brown, 
tough and elastic, of very great value; widely used in the 
manufacture of agricultural implements, boat oars, and car- 
riage shafts; in cabinet-work, for harness work, hoops, baskets, 
and clothespins. In rich soil. N. S. to Minn., Fla., Kan., and 
Texas. 

Order, Scrophulariales. 

Bignotviaccac, Bignonia Family. 

31. Paulownia Sieb. & Zucc. Paulownia. 

Trees with opposite petioled, palmately veined, simple 
leaves ; with superposed axillary buds ; and with large white 
pith, sometimes with cavities. 

Flowers in large panicles, bisporangiate, zygomorphic, tet- 
racyclic; stamens 4; fruit a capsule with numerous winged 
seeds. 

1., Paulownia tomentosa (Thumb.) Steud. Paulownia. 
A large rapid-growing tree with violet flowers in terminal pan- 
icles. Native of Japan; escaped from cultivation. N. Y. and 
N. J. to Ohio and Ga, 

32. Catalpa Scop. Catalpa. 

Trees with opposite or whorled, simple leaves with entire 
margins and with prominent green glands in the axils of the 
veins on the lower side. 



Treks of the Northern United States 


07 


Flowers large, white or mottled, in terminal panicles or 
corymbs, bisporangiate, zygomorphic; stamens usually 2 with 
3 prominent vestiges; capsule long and bean-like with nu- 
merous winged seeds. 

1. Young twigs glabrous or nearly so, leaf -blades downy 
below ; flowers large, white, with 2 yellow stripes 
inside and spotted purplish brown. 2. 

1. Young twigs and petioles with long hairs; leaf blades 

glabrous below or nearly so, commonly 3-lobed or 
angled, strong-scented, usually with 4 red oval glands 
at the base of the blade on the upper side; flowers 
small, yellow with orange stripes inside and violet 
spots ; capsule very slender. C. ovata, 

2. Bark thin, flaky ; young petioles glabrous or nearly so ; 

wings of seed usually narrowed at the ends, panicle 
many-flowered. C hignonioides. 

2. Bark thick and rough ; young petioles usually pubes- 
cent; wings of seed usually broad, the threads paral- 
lel ; panicle few-flowered. C. speciosa. 

1. Catalpa hignonioides Walt. Common Catalpa. A 
tree with thin flaky bark and spreading branches. Wood brown, 
soft, weak, durable in contact with the soil, much less valuable 
than that of C. speciosa. The flowers are said to produce irrita- 
tion of the skin. Gulf States. Escaped in the northern states 
as far as Ohio and N. Y. 

2. Catalpa speciosa Ward. Hardy Catalpa. A large 
rapid-growing tree with thick rough bark. Wood light, soft, 
not strong, brittle, of very coarse texture and brown in color, 
very durable in the ground; used for railroad ties, posts, fur- 
niture and interior finish; also suitable for paper pulp. 111. to 
Tenn., Mo., Ark., and Ohio. 

3. Catalpa ovafa Don. Japan Catalpa. A small tree, com- 
monly with 3-lobed or angled leaves. Flowers small. From 
Japan. Often cultivated. 



68 


Field Manual 


Subclass, Calyciflorae. 

Order, Rosales. 

Rosaccae. Rose Family. 

Amygdalatae. Peach Subfamily. 

33. Priinus (Tourii.) T... Apricot, Plum, Cherry. 
Shrubs or trees with alternate, simple, serrate, pinnately- 
veined leaves, with disk-like or tooth-like glands on the petiole ; 
with stipules or stipular scars, cylindrical pith, twigs some 
shade of brown, and with the fruit a drupe. 

Terminal bud prc.sent or self-pruned; perianth pentamcr- 
ous ; carpel 1, hypanthium deciduous; drupe mostly edible. 

1. Terminal bud usually present; leaves conduplicate in 
vernation; stone globose, little or not at all flattened; 
inflorescence racemose, corymbose, or umbellate. 2. 

1. Terminal bud self-pruned; leaves convolute in verna- 

tion ; stone of the drupe compressed ; inflorescence 
umbellate or with only 1 or 2 flowers. 7. 

2. Petioles usually not over I in. long; leaves ovate, ab- 

ruptly acute at the apex ; flowers corymbose, termi- 
nating twigs of the season. P, mahaleh. 

2. Petioles usually an inch or more long, or if not, the 

leaves not ovate; flowers in umbellate or somewhat 
corymbose clusters, or in racemes. 3. 

3. Flowers in umbellate or corymbose clusters. 4. 

3. Flowers in racemes. 6. 

4. Leaves glabrous or nearly so. 5. 

4. Leaves pubescent beneath, at least on the veins, with 

prominent hairs ; inflorescence umbellate ; drupe sweet. 
P, avium, 

0 . Leaves ovate-lanceolate to lanceolate ; inflorescence 
more or less corymbose; drupe with thin sour flesh. 
P. pcnnsylvanica. 

5. Leaves ovate to ovate-lanceolate; inflorescence umbel- 

late, drupe with thick sour flesh. P, cerasus. 

6. Leaves oval-lanceolate to ovate, acuminate or acute; 

glands on the petiole usually elongated and tooth-like ; 
bark black; drupe dark-purple or black, sweet. P. 
virginiana. 



Trees of the Northern United States 61> 

6. Leaves obovate to oval, abruptly acute or acuminate; 

glands on the petiole usually rounded or disk-like; 
bark gray; drupe red or purple, astringent. P. nana. 

7. Leaves abruptly acuminate, petiole much less than i as 

long as the blade. 8. 

7. Leaves abruptly long-acute or acuminate, ovate to 
round-ovate ; petiole i as long as the blade ; flowers 
solitary or in twos ; fruit velvety. P. armenujca. 

7. Leaves acute or obtusish, or gradually acuminate. 10- 

8. Leaves mostly broad and thick, somewhat pubescent or 

roughish beneath ; calyx lobes pubescent or glabrous 
within. 9. 

8. Leaves mostly narrow and peach-like, firm and more or 

less shining, glabrous; calyx lobes pubescent on both 
sides. P. hortulana. 

9. Calyx-lobes entire, pubescent within; fruit globose; 

flowers white. P. americam. 

9. Calyx lobes glandular-serrate, glabrous within ; fruit 
subglobose or oval ; flowers white, turning pink. P. 
nigra. 

10. Leaves glabrous when mature, acute or acuminate. 11. 

10. Leaves pubescent beneath, not pointed or only slightly 

so, ovate or obovate. P. domestica. 

11. Leaves lanceolate; drupe red with little or no bloom. 

P. angustifolia. 

11. Leaves ovate, drupe dark purple, with a bloom. P. alle-^ 
ghaniensis. 

Cherries, 

1. Prunus virgini^na L. Black Cherry. A large tree 
with rough, black, flaky bark; drupe globose, dark-purple or 
black, sweet but slightly astringent. Leaves oval, oval-lanceo- 
late, or ovate, acuminate or acute, serrate with appressed teeth. 
Leaves very poisonous to cattle, especially when half-wilted. 
Kernels very poisonous. Wood rather heavy, hard, strong, of 
fine texture, of a brown or reddish color ; much used in cabinet- 
work and interior finish, especially in cars and boats, also used 
in turnery. Self-prunes twigs: by means of cleavage planes in 
basal joints. Ont. to Fla., N. Dak., Kan., Tex., and Ohio. 



70 


Field Manual 


2. Prunus n^na Du Roi. Choke Cherry. A shrub or 
small tree with gray bark. Leaves obovate or broadly oval, 
abruptly acute or acuminate at the apex, rounded at the base, 
serrulate with slender teeth, glabrous or nearly so. Drupe red 
to nearly black, sometimes yellow, very astringent, not edible. 
Leaves poisonous ; kernels probably poisonous. Self-prunes 
leafy fruiting branches. Along river banks and in rocky places. 
Newf. to Man., Br. Col., Ga., Neb., Texas, Colo., and Ohio. 

3. Prunus mahaleb L. Mahaleb Cherry. A small tree 
with pale smooth bark. Leaves ovate, abruptly acute at the 
apex, rounded or slightly cordate at the base, denticulate, gla- 
brous, fragrant. Drupes with thin flesh and slightly flattened 
stone. From Europe. Conn, to Ont., N. Y. to Ohio and Kan. 

4. Prunus pennsylvanica L. f. Red Cherry. A small 
tree with sour globose, red drupes. Leaves oval or lanceolate, 
acute or acuminate, mainly rounded at the base, glabrous, ser- 
rulate. Leaves poisonous ; kernels probably poisonous. In rocky 
woods. Newf. to Ga., west to Rocky Mts. 

5. Prunus avium L. Sweet Cherry. A medium-sized 
tree with globose, black or dark red, sweet, edible drupes. 
Leaves ovate, oval, or slightly obovate, abruptly short-acumi- 
nate, irregularly serrate. Native of Europe. Ont. to Mass., 
Ohio and Va. 

6. Prunus cerasus L. Sour Cherry. A small tree 
with globose, red or reddish-black, sour, edible drupes. Leaves 
ovate or ovate-lanceolate, abruptly acute or acuminate, rounded 
at the base, very resinous when young. Self-prunes the fruiting 
branchlets. Native of Europe. N. H. and Mass, to N. Y. and 
Ohio. 

Plums and Apricot. 

7. Prunus armeniaca L. Apricot. A small round-topped 
tree with reddish bark. Drupe nearly smooth, short stalked, 
yellow, edible. Cultivated. 

8. Prunus americana Marsh. Wild Plum. A shrub 
or small tree with stunted thorn-like branches and thick black 
bark. Leaves ovate, or obovate sharply and often doubly ser- 
rate, rounded at the base, slender-petioled. Drupe with a tough 
skin, globose, red or yellowish, edible. Often used as a stock 



Trees of the Northern United States 


71 


on which to graft domestic plums. Wood hard, reddish in color. 
N. Y. to Mont., Fla., Colo., and Ohio. 

9. Prunus nigra Ait. Canada Plum. A tree with thin 
bark. Leaves oval, ovate, or obovate, long-accuminate, crenu- 
late-serrate ; drupe oval, orange-red, thick-skinned, with little 
or no bloom. Petals pink in age. Newf. to Man., Mass, and 
Wis. 

10. Prunus hortulana Bail. Wild-goose Plum. A 
small tree with spreading branches and thin bark. Leaves ovate- 
lanceolate to ovate, long-acuminate, closely glandular-serrate. 
Drupe bright red and thin-skinned, edible. 111. to Kan., Tenn., 
and Texas. 

11. Prunus angustifolia Marsh. Chickasaw Plum. A 
small tree with thorn-like stunted branches. Leaves acute, ser- 
rulate, often rounded at the base. Drupe globose, red, and 
edible. In dry soil. N. J. to Fla., west to Rocky Mts. 

1*J. Prunus domcstica L. Common Garden Plum. A 
small tree with about 100 cultivated varieties. Drupe of various 
colors, covered with a thick glaucous bloom. 

13. Prunus alleghaniensis Port. Alleghany Plum. A 
low shrub or small tree, seldom thorny. Leaves acute or acumi- 
nate, finely serrate, rounded at the base. Drupe pleasantly acid, 
globose-ovoid, with a conspicuous bloom. Penn, 

34. Amygdalus L. Peach. 

Trees or shrubs with alternate, simple, serrate, pinnately- 
veined leaves with 2-4 disk-like glands at the edge of the base 
of the blade, with terminal bud, stipular scars or stipules, red- 
dish or greenish twigs, and velvety drupe. 

Perianth pentamerous, carpel 1, hypanthium deciduous; 
drupe mostly edible with a deeply pitted stone. 

1. Amygdalus persica L. Peach. A small tree with 
beautiful pink or white flowers and a large edible drupe. Leaves 
with prominent nectar glands on the petiole or at the base of 
the blade. Leaves and kernels bitter, poisonous. Native of 
Asia; abundantly escaped. N. Y. to Fla. and Kan. 



72 


Field Manual 


Malatae. Apple Subfamily. 

35. Sorbus (Tourn.) L. Mountain-ash. 

Trees or shrubs with alternate, odd-pinnate leaves, terminal 
buds, cylindrical pith, and 3-5 bundlescars in the narrow leaf 
scar. 

Flowers bisporangiate ; fruit a small red berry-like pome, 
in compound cymes. 

1. Leaflets glabrous above. 2. 

1. Leaflets pubescent on both sides; calyx and pedicels 

usually woolly. S. aucuparia. 

2. Leaflets long-acuminate; fruit less than i in. in diam- 

eter. S. americana. 

2. Leaflets obtuse or short-pointed ; fruit more than i in. 

in diameter. S. scopulina. 

1. Sorbus americana Marsh. American Mountain- 
ash. A small tree with smooth bark. Bark and unripe fruit 
very astringent. Wood soft, light brown. In moist ground. 
Much prized for ornamental planting. Newf. to Man., N. Car., 
and Mich. 

2. Sorbus scopulina Greene. Western Mountain-ash. 
A small tree with smooth bark. In moist ground. Lab. to 
Alaska, N. Eng., Ohio, Mich., and in Rocky Mts. to Colo, and 
Utah. 

3. Sorbus aucuparia L. European Mountain-ash. A 
small tree, native of Europe. Frequently cultivated. Fruit 
poisonous to man, but eaten by some birds. N. S. to N. H. 

36. MMus Mill. Apple, Crab-apple. 

Trees or shrubs with alternate, simple, pinnately-veined, 
dentate, serrate or more or less lobed leaves, with stipules or 
stipular scars; with terminal buds, cylindrical pith, and fruit 
a pome without grit cells. 

Flowers bisporangiate with a fleshy hypanthium united with 
the ovulary, pentamerous, stamens numerous. 

1. Leaves glabrous, at least when mature. 2. 

1. Leaves persistently pubescent or tomentose beneath. 3. 

2. Leaves oblong, oval, or lanceolate, narrowed at the 

base. M, angustifolia. 



Trees of the Northern United States 


73 


2. Leaves ovate, rounded or cordate at the base, often 
somewhat lobed. M. coronaria. 

2. Leaves ovate, acute or acuminate at the apex and 

acute at the base, on slender petioles ; finely and 
nearly evenly serrate. M. Daccafa. 

3. Leaves mostly narrowed at the base ; pome 1-2 in. in 

diameter. M. ioensis. 

3. Leaves rounded or cordate at the base; pome usually 
large, 2-4 in. in diameter. M, sylvesfris. 

1. Malus angustifdlia (Ait.) Mx, Narrow-leaf Crab- 
apple. A small tree usually with thorn-like stunted branches or 
spurs. Leaves oblong, oblong-lanceolate, or oval, thick, shining 
above, sometimes pubescent beneath when young, dentate or 
often entire. Wood hard, reddish-brown. On low ground. N. J. 
to 111., Kan., Fla., and La. 

2. Malus baccata (L.) Borkh. Siberian Crab-apple. A 
small spreading tree with compact crown. Pedicles very slen- 
der ; fruit small, not becoming mellow. Cultivated. 

3. Malus coronaria (L.) Mill. Fragrant Crab-apple. 
A small tree with hard and sour fruit suitable for preserving. 
Leaves ovate, to triangular-ovate, sparingly pubescent beneath 
when young, sharply serrate and often somewhat lobed. Wood 
soft and reddish-brown. On low ground. Ont. to Mich., 
S. Car,, Iowa, and Kans. 

4. Malus ioensis (Wood) Britt. Iowa Crab-apple. A 
small tree much resembling M. coronaria. Leaves ovate, 
oval, or oblong, dentate, crenate or with a few rounded lobes, 
white pubescent beneath, at length glabrous above. Minn., Wis., 
and 111., to Neb., Ky., La., and O'kla. 

5. Malus sylvestris Mill. M, malus (L) Britt. 
Common Apple. A medium-sized tree with spreading branches. 
Leaves ovate or oval, glabrous or nearly so above, pubescent 
and often woolly beneath. Fruit large, various. Introduced from 
Europe and escaped in many places. The seeds are poisonous. 
Me. to N. Y., N. J., Ohio, and Ga. 

37. Pyrus (Tourn.) L. Pear. 

Trees or shrubs with alternate, simple, pinnately-veined, 
serrate leaves with long petioles; with stipules or stipular 



74 


Field Manual 


scars ; with terminal buds, cylindrical pith, and fruit a pome 
with grit cells. 

Flowers bisporangiate with a fleshy hypanthium united with 
the ovulary ; pentamerous ; stamens numerous. 

1. Pyrus communis L. Pear. A pyramidal usually 
slender tree, often with thorn-like stunted branches. Bark 
smooth. Wood hard, fine-grained, reddish-brown. Cultivated 
for its large fleshy fruit. Native of Europe and Asia. Me. to 
N. J. and Ohio. 

38. Cydonia Tourn. Quince. 

Shrubs or low small trees, our cultivated species with 
alternate, simple, pinnately veined, entire, deciduous leaves with 
stipules or stipular scars; cylindrical pith, and with fruit a 
pome containing many seeds in each cavity. 

Flowers bisporangiate, perianth pentamerous, pome fleshy. 

1. Cydonia obldnga Mill. Quince. A low tree with 
crooked stem and rambling branches. Cultivated for the large 
sour fleshy fruit. 

39. Amelanchier Medic. Juneberry. 

Shrubs or small trees with alternate, simple, serrate, pin- 
nately- veined leaves ; with 3 bundle scars, terminal bud, a nar- 
row leaf scar, and fruit a berry-like pome. 

Flower bisporangiate, perianth pentamerous, pome small 
with twice the number of cavities as styles. 

1. Leaves acute or acuminate at the apex ; top of the 
ovulary glabrous or nearly so. 2. 

1. Leaves rounded, obtuse or subacute at the apex; top 

of the ovulary woolly; petals in. long. A san- 
guinea. 

2. Leaves glabrous when mature, but pubescent or woolly 

when young, ovate to ovate-lanceolate; base cordate 
or rounded. A canadensis. 

2. Leaves densely white-woolly beneath, at least when 
young, oblong to obovate, rarely sub-cordate at the 
base. A. intermedia. 

1. Amelanchier canadesis (L.) Med. Common June- 
berry. A medium-sized tree with a small, red or purple, sweet 



Trees of the Northern United States 


75 


and edible, berry-like pome. Wood very hard, brown. In dry 
soil. Nova Scotia to Ont., Fla., La., and Ark. 

2. Amelanchier interm^ia Spach. Swamp Juneberry. 
A shrub or small tree growing in swamps and moist soil. Vari- 
able. N. Eng. to Ont., Fla., and La. 

3. Amelanchier sanguinea (Pursh) DC. Roundleaf 
Juneberry, A tall shrub or small tree growing in woods and 
thickets. N. B. to Minn., N. C., and Mich. 

40. Crataegus L. Hawthorn. 

Small trees or shrubs with simple, serrate or lobed leaves, 
with stipules or stipular scars, and usually with typical axillary 
thorns, but without terminal thorns. 

Flowers bisporangiate, i^rianlh pentamerous, stamens 5-25; 
pome drupe-like with bony ripe carpels. 

The species of Crataegus arc at present in a very unsatis- 
factory condition. Probably many of those included below are 
merely hybrids or forms of freely interbreeding elementary 
varieties. Many of the specific English names are also unsatis- 
factory. W. W. Eggleston’s treatment of the species of the 
northeastern United States is mainly followed below. 

Required for identification, the leaves and fruit. 

1. Leaves not deltoid-cordate. 2. 

1. Leaves conspicuously deltoid-cordate, glabrous. (Cor- 

datae). 55. 

2. Leaves glabrous, glabrous above and pubescent beneath, 
or pubescent on both sides. 3. 

2. Leaves pubescent above, glabrous beneath; thorns i-1 

in. long; fruit black, (Douglasianae). 54. 

3. Petioles i in. long or longer. 4. 

3. Petioles less than i in. long. (Parvifoliae). 53. 

4. Leaves not deeply cut. 5. 

4. Leaves deeply cut, lobes numerous; thorns less than 1 

in. long. (Oxyacanthae). 52. 

5. Leaves broadest at the middle or apex, cuneate. 6. 

5. Leaves broadest at the base. 12. 

6. Leaves broadest toward the apex. 7. 

6. Leaves broadest at the middle. 8. 



76 


Field Manual 


7. Leaves shining, not impressed- veined above. (Crus- 
galli). 14. 

7. Leaves dull, impressed-veined above. (Punctatae). 18. 

8. Petioles usually glandless, or if so then the nutlets 

pitted on the ventral faces. 9. 

8. Petioles always with small stalked glands along their 

entire length; nutlets without ventral pits. (Intri- 
catae). 30. 

9. Calyx - lobes glandular - laciniate, glandular - serrate, or 

glandular-margined. 10. 

9. Calyx-lobes not glandular-margined; leaves not im- 
pressed - veined, often trilobed towards the apex. 
(Virides). 29. 

10. Leaves impressed-veined. 11. 

10. Leaves not impressed-veined, elliptic ovate to orbicular ; 

calyx-lobes glandular-margined ; leaves not trilobate 
(Rotundifoliae). 24. 

11. Leaves rhombic-elliptic; calyx-lobes usually deeply cut; 

nutlets deeply pitted on the ventral faces. (Macra- 
canthae). 21. 

11. Leaves elliptic to ovate; calyx-lobes less deeply cut; 

nutlets with shallow pits on the ventral faces. (Brain- 
erdianae). 23. 

12. Leaves in. long and wide, membranous ; calyx-lobes 

usually entire. 13. 

12. Leaves 1-4 in. long and wide; calyx-lobes usually ser- 

rate. (Coccineae). 44. 

13. Leaves yellow-green often slightly pubescent; fruit soft 

at maturity. (Tenuifoliae). 34. 

13. Leaves blue-green, usually glabrous; fruit hard at ma- 

turity. (Pruinosae). 38. 

Crus-galli. — 

14. Leaves not lobed. 15. 

14. Leaves somewhat lobed. 16. 

15. Leaves 1-4 in. long. C. crus-galli. 

15. Leaves 1-21 in. long. C. herherifolia, 

16. Styles and nutlets usually 2. C. schisophylla. 

16. Styles and nutlets usually 3-5. 17. 



Trees of the Northern United States 


77 


17. Lobes of the leaves irregular, obtuse; fruit globose. 
C. denaria. 

17. Lobes of the leaves regular, acute ; calyx-lobes serrate. 

C. fccunda. 

— Punctatae. — 

18. Fruit ellipsoidal; nutlets usually 3 or 4. 19. 

18. Fruit globose. 20. 

lib Leaves bright yellow-green, slightly impressed- veined 
above. C. cunciformis. 

19. Leaves dull gray-green, strongly imprcssed-vcined 

above, obovate, narrow. C. punctata. 

20. Nutlets 2 or 3. C. margaretta. 

20. Nutlets 4 or 5. C. suborbiculata. 

— ilf acracanthae. — 

21. Leaves dark green, glabrous and shining above, cori- 

aceous. 22. 

21. Leaves gray-green, pubescent and dull above, subcori- 

aceous, rhombic-ovate, lobed. C. calpodcndron. 

22. Fruit ^ in. thick or less; leaves large. C. succxdcnta. 

22. Fruit I in. thick or less ; leaves small. C. neoflui/ialis. 

— Brainerdianae. — 

23. Fruit and corymbs pubescent ; calix-lobes sharply glan- 

dular-serrate ; leaves serrate ; styles and nutlets 2 or 
3. C. pertomentosa. 

23, Fruit and corymbs glabrous; calix-lobes remotely glan- 

dular-serrate. C. brainerdi. 

— Rotnndifoliae. — 

24. Leaves longer than wide. 25. 

24. Leaves about as wide as long. 26. 

25. Leaf lobes acuminate. C. laurentiana. 

25. Leaf lobes acute. C. lucorum. 

26. Leaf -lobes acuminate. C. irrasa. 

26. Leaf-lobes acute or obtuse. 27. 

27. Calyx-tube prominent ; fruit subglobose. C. macau- 

leyae. 

27. Calyx-tube obscure. 28. 

28. Leaves acutely lobed toward the apex ; calyx-lobe.s 

glandular-laciniate. C, bicknellii. 

28. Leaves not acutely lobed ; calyx -lobes glandular m. 



78 


Field Manual 


gined only ; fruit globose, red, round in cross section. 
C. chrysocarpa. 

— Virides. — 

20. Leaves ovate ; lobes shallow ; fruit yellow-red. C. 
ovata, 

29. Leaves oblong-ovate, lobes deep; fruit bright red, glau- 

cous. C. viridis. 

— Intricatae. — 

30. Foliage and fruit pubescent; corymbs villous. 31. 

30. Foliage, fruit, and corymbs glabrous. 32. 

31. Fruit globose, greenish to reddish-brown. C. intricata. 

31. Fruit ellipsoid or pyriform, yellow. C. stonei. 

32. Leaves cordate, lobed. C. populifolia. 

32. Leaves cuneate, lobed. 33. 

33. Leaves elliptic-ovate; fruit pyriform-ellipsoid. C. stra- 

mine a. 

33. Leaves ovate to oval ; fruit globose or subglobose, red- 

dish-green to reddish-brown. C. boyntoni. 

— T ennifoliae. — 

34. Fruit ellipsoid, ovoid, or pyriform; calyx-lobes entire. 

35. 

34. Fruit compressed-globose or subglobose. 30. 

35. Leaves much lobed; fruit small, in. thick, with 

rather firm flesh. C. roanensis. 

35. Leaves not conspicuously lobed ; fruit large ; i -4 in. 

thick, with soft flesh. C. nmcrospenna. 

30. Lobes of the leaves reflexed. C. grayana. 

36. Leaf-lobes spreading or ascending. 37. 

37. Terminal leaves cuneate. C. alnornm. 

37. Terminal leaves cordate. C. populnea. 

— Pruinosae. — 

38. Leaves elliptic-ovate. C. jesupi. 

38. Leaves ovate. 39. 

39. Leaves usually cordate. 40. 

39. Leaves usually cuneate. 41. 

40. Fruit conspicuously angled, strongly pruinose. C. ru- 

gosa. 

40. Fruit not conspicuously angled, only slightly pruinose. 
C. filipes. 



Trees of the Northern United States 


79 


41. Lobes of the leaves deep, acuminate. C. leiophylla. 

41. Lobes of the leaves shallow, acute. 42. 

42. Fruit without conspicuous angles. C. beata. 

42. Fruit conspicuously angled. 43. 

43. Leaves deltoid. C. gattingcri, 

43. Leaves ovate. C. pruinosa. 

— Coccincae. — 

44. Mature leaves usually glabrous above ; young foliage 

bronze-green. 45. 

44. Mature leaves tomentose above ; young foliage yellow- 

green. 50. 

45. Leaves oblong-ovate. 46. 

45. Leaves broadly ovate. 47. 

46. Corymbs nearly glabrous. C. znllipes. 

46. Corymbs very pubescent. C. anomala. 

47. Corymbs and fruit glabrous. C. coccinioidcs. 

47. Corymbs and fruit pubescent or tomentose. 48. 

48. Leaves on the vegetative shoots cuneate. 49. 

48. Leaves on the vegetative shoots cordate. C. albicans. 

49. Leaves concave, 1.1-3 in. long, lJ-21 in. wide. C. 

pringlci. 

49. Leaves plane 1]-1 in. long, ll-3i in. wide. C. coc- 

cinca. 

50. Leaves on the vegetative shoots cuneate at the base. 

51. 

50. Leaves on the vegetative shoots cordate. C. mollis. 

51. Lobes of the leaves broad, shallow, acuminate. C. ar- 

noldiana, 

51. Lobes narrow, deep, and acute; fruit ellipsoid-pyriform. 

C. submollis. 

— Oxyacanihae. — 

52. Leaves ovate, 3-15-lobed or cleft. C. monogyna. 

— Parvifoliae. — 

53. Leaves small, subcoriaceous, corymbs 1-3-flowered. C. 

uni flora. 

— Douglasianae. — 

54. Leaves subcoriaceous, petioles 1-1 in. long. C, doug^ 

lasii. 



80 


Field Manual 


— Cordatae. — 

55. Leaves often conspicuously 3-5-lobed, petioles i-2 in. 
long. C. phacnopyrum. 

1. Crataegus crus-galli L. Cockspur Hawthorn. A 
small tree with spreading branches and numerous slender 
thorns. Leaves coriaceous shining, above, sharply serrate. Fruit 
ellipsoid-ovoid to subglobose, greenish to red, flesh hard, re- 
maining on the branches until late in the winter. The best 
hawthorn for hedges. N. Y. to Out., south to Conn., Ga., 
and Kan. 

2. Crataegus berberifolia T. & G. Barberry-leaf 
Hawthorn. A small tree with spreading branches and a broad 
crown, with few thorns. Leaves oblong-cuneiform, spatulate, 
or obovate, rough-pubescent above, white-pubescent or tomen- 
tose beneath. Fruit subglobose to short-ellipsoid, yellow, or- 
ange, or red. Ky. to Mo. and the Gulf States. 

3. Crataegus schizophylla Eggl. Martha’s Vineyard 
Hawthorn. A small tree with irregular ascending branches 
and numerous thorns. Leaves oblong-ovate to ovate, coarsely 
serrate with short acute lobes toward the apex, glabrous, 
slightly impressed-veined. Fruit pyriform-ellipsoid, dark red; 
nutlets ribbed on the back. Mass. 

4. Crataegus denaria Beadle. Palmer’s Hawthorn. 
A small tree with spreading branches and a round-topped 
crown. Leaves oval, ovate, or oblong-ovate, often slightly 
lobed towards the apex. Fruit globose or subglobose, reddish- 
green or light red. In low rich soil. Ky. to Mo. and Miss. 

5. Crataegus fecunda Sarg.. Fruitful Hawthorn. A 
small tree with spreading branches and numerous thorns. 
Leaves oblong-obovate to oval. Fruit short-ellipsoid to sub- 
globose, orange-red, slightly pubescent. Rich bottom lands. 
III. and Mo. 

6. Crataegus cuneifdrmis (Marsh.) Eggl. Marshall’s 
Hawthorn. A small tree with widely spreading branches, dark 
brown scaly bark, and numerous, often branched thorns. Leaves 
oblanceolate-obovate. Fruit ellipsoid-pyriform, scarlet or dark 
red. N. Y. and Pa. to Va. and 111. 

7. Crataegus punctslta Jacq. Dotted Hawthorn. A 



Trees of the Northern United States 


81 


small flat-topped tree with horizontal or ascending branches 
and light gray thorns. Leaves obovate, serrate, doubly serrate, 
or lobed at the apex. Fruit short-ellipsoid, yellow or red, 
somewhat edible. Quebec to Pa., Minn., Iowa, and Ky. 

8. Crataegus margaretta Ashe. Margaret’s Hawthorn. 
A shrub or small tree wuth ascending branches forming a round 
crown. Leaves oblong-obovate to ovate, serrate or doubly ser- 
rate, usually somewhat lobed. Fruit dull rusty green, yellow, 
or red, compressed globose to short ellipsoid, angular. Ont. 
to Iowa, Mo., Tenn., and Va. 

9. Crataegus suborbiculata Sarg. Caughuawaga 
Hawthorn. A small tree with spreading branches and a 
broad crown. Leaves ovate-orbicular, serrate or doubly 
serrate. Fruit globose or comprcsscd-globose, dull green 
to scarlet. In limestone areas. Montreal to Mich. 

10. Crataegus succulenta Schrad. Longthorn Haw- 
thorn. A small tree with ascending branches forming a broad 
irregular crown, and with numerous bright, brown thorns. 
Leaves rhombic-ovate to obovate, doubly serrate and usually 
somewhat lobed toward the apex. Fruit globose or short- 
elipsoid, dark red. N. S. to Minn., N. C., Neb., and Colo. 

11. Crataegus neofluviMis Ashe. New River Haw- 
thorn. A small tree with ascending and spreading branches, 
and numerous thorns. Leaves elliptic-ovate to obovate, doubly 
serrate and somewhat lobed towards the apex, coriaceous, dark 
green and shining above. Fruit globose or short-ellipsoid, 
dark red. Vt, to Wis., N, C., and Iowa. 

12. Crataegus calpodendron (Ehrh.) Medic. Pear 
Hawthorn. A shrub or small tree with ascending and spread- 
ing branches forming a broad crown, with stout thorns and 
tomentose twigs. Leaves rhombic-ovate, acute or acuminate at 
the apex, doubly serrate. Fruit pyriform or ellipsoid, orange- 
red or red, N. Y. and N. J. to Minn, and Mo. 

13. Crataegus pertomentosa Ashe. Prairie Hawthorn. 
A small tree with nearly horizontal branches forming a flat- 
tened crown and with numerous curved thorns. Leaves oblong 
to obovate, finely doubly serrate or lobed. Fruit globular or 
nearly so, cherry-red, villous when young. Rocky soil. Iowa, 
Mo., and Kan. 



Field Manual 




14. Crataegus brainerdi Sarg. Brainerd's Hawthorn. 
A shrub or small tree with ascending branches. Leaves elliptic 
to ovate, finely doubly serrate or lobed. Fruit short-ellipsoid 
to globose, cherry-red to scarlet. N. Eng. to Iowa and Pa. 

15. Crataegus laurentiana Sarg. Fcrnald’s Hawthorn. 
A large, much-branched shrub or small tree with long thorns. 
Leaves oblong to oblong-ovate, sharply doubly serrate or lobed. 
Fruit ellipsoid, dark crimson. Newf., N. S., Quebec, Me., and 
shores of Lake Superior. 

16. Crataegus lucorum Sarg. Grove Hawthorn. A 
shrub or small tree with ascending branches. Leaves oblong- 
ovate to broadly ovate, doubly serrate or lobed. Fruit pyri- 
form-ellipsoid, crimson. 111. and Wis. 

17. Crataegus irrasa Sarg. Blanchard’s Hawthorn. 
A shrub or small tree with numerous spines. Leaves ovate to 
elliptic, doubly serrate or lobed. Fruit subglobose to short- 
ellipsoid, red or scarlet, somewhat pubescent. Quebec to Vt. 
and N, Y. 

18. Crataegus macauleyae Sarg. Macauley’s Haw- 
thorn, A small round-topped tree with somewhat pendulous 
branches. Leaves ovate to oval, doubly serrate or lobed. Fruit 
subglobose to short-ellipsoid, dark crimson. N. Y. 

19. Crataegus bicknelli Eggl. BickncITs Hawthorn. 
A round-topped shrubby tree with numerous stout thorns. 
Leaves ovate or oblong-ovate, sharply doubly serrate and lobed. 
Fruit globose, red. Mass. 

20. Crataegus chrysocarpa Ashe. Roundleaf Haw- 
thorn. A beautiful, round-topped shrub or small tree with nu- 
merous thorns. Leaves ovate-orbicular or obovate, doubly ser- 
rate or lobed, shining above. Fruit depressed-globose to short- 
ovoid, red. N. S. and N. B. to Saskatch., .south to N. C, Neb., 
and N, M. 

21. Crataegus ovata Sarg. Ovate-leaf Plawthorn. A 
tree with yellow scaly bark. Leaves ovate-elliptic or O'bovate, 
coarsely serrate or doubly serrate, often somewhat lobed to- 
wards the apex, dark green and shining above. Fruit globose 
or compressed-globose, yellow to orange-red. River bottoms. 
Ky. and Mo. 



Trees of the Northern Uniter States 


83 


22. Crataegus viridis L. Green Hawthorn. A tree with 
ascending branches and a broad crown, often without thorns. 
Leaves oblong ovate, serrate or doubly serrate, often lobed to- 
ward the apex, dark green and shining above. Fruit globose 
or compresscd-globosc, bright red or orange, glaucous. Allu- 
vial soil. Va. to Fla., Ind., 111., Kan., and Texas. 

23. Crataegus intricata Lange. Biltmorc Hawthorn. 
An irregularly branched shrub or small tree with few thorns. 
Leaves elliptic-ovate to broadly ovate, doubly serrate or lobed, 
rough-pubescent. Fruit short-ellipsoid to globose, greenish, 
yellow or becoming dark reddish-brown, somewhat pubescent. 
Open rocky woods. N. Eng. and N. Y., south to S. Car. and 
Mo. 

24. Crataegus stonei Sarg. Stone’s Hawthorn. A 
much-branched shrub or small tree with prominent 
thorns. Leaves oblong to oblong-ovate, doubly serrate or 
lobed. Fruit pyriform to short-ellipsoid, light yellow or 
yellow-green tinged with red. Rocky soil. Mass., Conn., 
and N. Y. 

25. Crataegus populifolia Walt. Poplar-leaf Haw- 
thorn. A shrub or small tree with ascending and spreading 
branches forming a round crown. Leaves deltoid-ovate or ob- 
long-ovate, serrate or doubly serrate with acute lobes. Fruit 
globose, light red, without angles. Va. to S. C. 

26. Crataegus strammea Beadle. Allegheny Haw- 
thorn. An irregularly branched shrub or small tree with oc- 
casional thorns. Leaves elliptic-ovate, doubly serrate or lobed. 
Fruit pyriform to ellip.soid, angular, yellow-green. Rocky hills. 
Vt. to Mich., south to Del., Ala., and Mo. 

27. Crataegus boyntoni Beadle. Boynton’s Hawthorn. 
A round-topped, irregularly branched shrub or small tree with 
occasional thorns. Leaves oval to ovate, doubly serrate or 
slightly lobed. Fruit subglobosc, orange-red or red-brown. 
Shaly soil. Mass, to Mich., south to S. C. and Tenn. ^ 

28. Crataegus roanensis Ashe. Roan Mountain Haw- 
thorn. A shrub or small tree with ascending branches and nu- 
merous curved thorns. Leaves ovate or oblong-ovate, serrate 
with acute straight lobes. Fruit ellipsoid, ovoid, or pyriform, 
crimson. Quebec to Wis., N. C., and Tenn. 



84 


Field Manual 


29. Crataegus macrosperma Ashe. Variable Haw- 
thorn. A shrub or ^small tree with ascending branches and 
numerous thorns. Leaves elliptic-ovate to broadly ovate, 
doubly serrate and somewhat lobed. Fruit ellipsoid or pyri- 
form, scarlet to crimson, often glaucous. N. S. and Ale. to 
Minn., N. C. and Tenn. 

30. Crataegus grayana Eggl. Gray’s Hawthorn. A 
large shrub or small tree with ascending branches. Leaves 
ovate, doubly serrate with 4-0 pairs of acuminate lobes. Fruit 
subglobose to short ellipsoid, angular, dark cherry-red. N. 
Eng. to Out. and N. V. 

31. Crataegus alnorum Sarg. Ed.son’s Hawthorn. A 
broad shrub or small tree with ascending branches. Leaves 
ovate, serrate or doubly serrate with acute lobes. Fruit sub- 
globose, slightly angular, dark cherry-red. N. Eng. to Mich 
and Pa. 

32. Crataegus populnea Ashe. Gruber’s Hawthorn. 
A shrub or small tree with flattened round crown. Leaves 
broadly ovate to elliptic-ovate, slightly villous, serrate or 
doubly serrate, sometimes lobed. Fruit glabrous, short-ellip- 
soid, scarlet. Low ground. Ont. to Pa. and Del. 

33. Crataegus jesupi Sarg. Jesup’.s Hawthorn. A 
large shrub or small tree with ascending branches. Leaves el- 
liptic-ovate, serrate or doubly serrate with 4 to 5 pairs of acute 
lobes. Fruit short-ellipsoid to pyriform, slightly angled, dark 
red. Vt. to Wis. south to Pa. 

34. Crataegus rugosa Ashe. Rugose Hawthorn. A 
shrub or small tree with ascending branches. Leaves broadlv 
ovate, serrate or doubly serrate with 4-0 pairs of broad acu- 
minate lobes, glabrous. Fruit depressed-globose, bright red. 
Conn, to Pa., Ind., and N. C. 

35. Crataegus filipes Ashe. Beckwith’s Hawthorn. 
A shrub or small tree with ascending branches and numerous 
thorns. Leaves ovate, serrate or twice serrate and lobed, glab- 
rous. Fruit globose or compressed-globose, cherry-red. West- 
ern N. Eng. to Mich, south to Pa. 

36. Crataegus leipophylla Sarg. Maine’s Hawthorn 
A large shrub or small tree with erect branches and numerous 



Trees of the Northern United States 


85 


thorns. Leaves broadly ovate, doubly serrate, with 3-5 pairs 
of acuminate spreading loibes, dull. Fruit pyriform to globose, 
slightly angular, bright or dark scarlet. N. Y. to Pa. 

37. Crataegus beata Sarg. Dunbar’s Hawthorn. A 
shrub or small tree with ascending or erect branches. Leaves 
ovate, doubly serrate with acute lobes, dull. Fruit short-ellip- 
soid, slightly angular, crimson. Ont. to Pa. 

38. Crataegus gattmgeri Ashe. Gattinger’s Hawthorn. 
A shrub or small tree with ascending branches forming an ir- 
regular crown, and with numerous thorns. Leaves narrowly 
ovate to deltoid, serrate or doubly serrate, lobed toward the 
apex, glabrous, dark green above. Fruit globose, angular, red. 
Pa. to Ind., south to W. Va. and Tcnn. 

39. Crataegus pruinosa (Wendl.) Koch. Waxy-fruited 
Hawthorn. A shrub or small tree with ascending branches, 
irregular crown, and numerous slender thorns. Leaves elliptic- 
ovate to broadly ovate, doubly serrate with 3 or 4 pairs of 
broad acute lobes toward the apex, glabrous. Fruit depressed- 
globose or short-ellipsoid, strongly angled, pritinose, scarlet or 
purple. Rocky open woods. N. Eng. to Mich., N. C. and Mo. 

40. Crataegus villipes Ashe. Thinleaf Hawthorn. A 
tree with strongly ascending branches. Leaves elliptic-ovate, 
serrate or doubly serrate with 4-G pairs of acute or acuminate 
lobes, pubescent or scabrous. Fruit pyriform or ellipsoid, crim- 
son. Maine to Quebec to Mich., south in the mountains to 
N. C. 

41. Crataegus anomala Sarg. Oblong-leaf Hawthorn. 
A shrubby tree with numerous thorns. Leaves oblong to ovate, 
serrate or doubly serrate with acute lobes. Fruit pyriform-el- 
lipsoid, crimson. Quebec to Mass, and N.* Y. 

42. Crataegus coccinioides Ashe. Eggert’s Haw- 
thorn. A shrub or small tree with spreading branches. 
Leaves broadly ovate, doubly serrate, dark green above. 
Fruit sub-globose, obtusely angled. Quebec to R, L, west 
to Mo. and Kan. 

43. Crataegus pringlei Sarg. Pringle’s Hawthorn. A 
small tree with ascending branches. Leaves ovate to oval, 
doubly serrate, with shallow lobes. Fruit short-ellipsoid to 



80 


Field Manual 


pyriform, pumbescent, red. Western N. Eng. to 111., south to 
Pa. 

44. Crataegus coccmea L. Scarlet Hawthorn. A 
small tree with ascending and spreading branches and stout 
short thorns. Leaves broadly ovate, acute or acuminate at the 
apex, broadly cuneate or truncate at the base, doubly serrate 
or lobed, somewhat scabrous. Fruit pyriform to short ellip- 
sod, red, somewhat edible. Of considerable decorative value. 
Conn, to Ont., 111., Hcl. and Pa. 

45. Crataegus albicans Ashe. Tatnall’s Hawthorn. A 
shrub or small tree with spreading branches. Leaves broadly 
ovate to oblong-ovatc, doubly serrate or lobed. Fruit subglo- 
bose or somewhat pyriform, dark red. Western N. Eng. to 
Mich., south to Del. and Tenn. 

46. Crataegus arnoldiana Sarg. Arnold’s Hawthorn. 
A small tree with ascending branches, forming a broad crown, 
and numerous long thorns. Leaves broadly ovate to oval, ser- 
rate or doubly serrate with broad shallow lobes, tomentose or 
scabrous above. Fruit globose or subglobose, bright crimson, 
slightly pubescent; flesh thick, juicy, and edible. Mass, and 
Conn. 

47. Crataegus submollis Sarg. Emerson’s Hawthorn. 
A small tree with spreading branches, forming a broad sym- 
metrical crown, and with numerous thorns. Leaves ovate, 
doubly serrate and acutely lobed, tomentose, becoming scabrate. 
Fruit short-ellipsoid to pyriform, orange-red, slightly tomen- 
tose, edible. Quebec to Mass, and N. Y. 

48. Crataegus mollis (T. & G.) Scheele. Downy Haw- 
thorn. A tree with spreading branches and densely pubescent 
twigs, forming a broad-topped crown. Leaves broadly ovate, 
doubly serrate with narrow acute lobes, densely tomentose. 
Fruit short-ellipsoid to subglobose, scarlet, edible. Ont, to S. 
Dak., Tenn., and Ark. 

49. Crataegus monogyna Jacq. English Hawthorn. 
A shrub or tree with ascending branches and numerous thorns. 
Leaves ovate, sharply 3-15 lobed or cleft, dark green and gla- 
brous above when mature. Fruit globose or subglobose, red. 
Native of Europe. Sparingly escaped in the eastern states. 

50. Crataegus unifldra Muench. Dwarf Hawthorn. An 



Trees of the Northern United States 


87 


irregular shrub or small tree with numerous, slender, straight 
thorns. Leaves obovale to spatulate, crenate or crenate-serrate, 
shining above. Corymbs 1-3 flowered. Fruit ellipsoid, pyri- 
form or globose, greenish-yellow or red. In sandy soil. N. Y. 
to Fla., west to W. Va., Mo., and Tex. 

51. Crataegus douglasii Lindl. Douglas’ liawthorn. 
A shrub or tree with dark brown scaly bark and short thorns. 
Leaves ovate to obovate, doubly serrate and lobed, dark green 
and pubescent above. Fruit short-ellipsoid, dark purple ; flesh 
soft, sweet. From Mich, northwestward. 

52. Crataegus phaenopyrum (L.f.) Medic. Washing- 
ton Hawthorn, A shrub or small tree with strongly ascending 
branches, and numerous thorns. Leaves ovate-triangular 
simply or doubly serrate, often 3-5 lobed, bright green and 
glabrous above. Fruit depressed-globose, scarlet. Moist rich 
ground. A very desirable species for cultivation. Va. to Ga., 
III., and Ark. Naturalized northward to N. J., Pa., and Ohio. 

Fabaceae. Bean Family. 

Cassiatac. Senna Sufamily. 

41. Gymnocladus Lam. Coffee-bean. 

Trees with alternate, evenly bipinnate leaves, sunken super- 
posed axillary buds, and large chocolate-colored pith. 

Flowers greenish, diecious, both types with vestiges of the 
opposite sporopliylls ; fruit a woody bean, 

1. Gymnocladus dioica (L.) Koch. Coffee-bean. A 
large, slow-growing tree with rough bark and few branches. 
Bean short and thick, the greenish pulp within poisonous. The 
bruised leaves are used as a fly poison, and the seeds have been 
used as a substitute for coffee. Wood compact, heavy, rather 
soft, strong, tough, reddish in color, of coarse texture, and 
taking a good polish; used to some extent in cabinet-work. In 
rich soil. Ont. to Ohio and Penn., Tenn., S. Dak., and 0kla. 

42. Gleditsia L. Honey-locust. 

Trees with alternate, evenly pinnate or bipinnate leaves, 
superposed buds beneath the petiole base, and usually with 
branched axillary thorns. 



8S 


Field Manual 


Flowers small, greenish, imperfectly monosporangiate and 
diecious; fruit a bean. 

1. Pod linear-oblong, many seeded, pulpy within; leaflets 
short-stalked, oblong-lanceolate or oval, obtuse at 
both ends, inequilateral at the base. G. triacanthos. 

1. Pod obliquely oval, 1-seeded, not pulpy; leaflets thicker, 
darker green, usually larger, ovate-lanceolate or lan- 
ceolate, the margin more crenulate. G. aqimtica. 

1. Gleditsia triacanthos L. Honcy-locust. A large 
tree of rapid growth, usually with stout branching or simple 
thorns and with rough bark, the catkin-like racemes often ap- 
pearing on the main trunk and larger branches. Used as a 
hedge plant. Autumn leaves pure yellow. Wood heavy, hard, 
strong and tough ; used for fencing, fuel and wagon hubs. 
Sprouts freely from the roots if disturbed by plowing. Grows 
well in dry or sandy soil. Ont. and N. Y. to S. Dak., Ga., 
Kan., and Texas. 

2. Gleditsia acquatica Marsh. Water Honey-locust. A 
tree growing in swamps. Thorns usually little branched. Wood 
very hard and bright reddish-brown. Ind. to Mo., S. Car., 
Fla., and Texas. 

43. Cercis L. Redbud. 

Trees or shrubs with 2- ranked, entire, palmately veined 
leaves. 

Flowers zygomorphic in short lateral fascicles; stamens 
10, distinct; fruit a flat bean. 

1. Cercis canadensis L. Redbud. A small tree with 
bright red-purple flowers before the leaves; fine for orna- 
mental purposes. Wood hard and heavy, beautifully varie- 
gated. In rich soil. Easily cultivated. Ont. and N. Y. to 
Iowa, Neb., N. J., Fla., and Texas. 

Fabatae. Bean Subfamily. 

44. Cladrdstis Raf. Yellow- wood. 

Trees with alternate, odd-pinnate leaves with entire leaf- 
lets, with the petiole base covering the superposed buds, and 
without milky or resinous sap. 

Flowers white, showy, fragrant; fruit a slender bean. 



Trees of the Northern United States 


89 


1. Cladrastis lutea (Mx. f.) Koch. American Yellow* 
wood. Trees with smooth bark, close like in the beech. Wood 
light-yellow. In rich soil; much planted. Ky., Mo., Tenn., 
and N. Car. 

45. Robmia L. Locust. 

Trees or shrubs with alternate odd-pinnate non-punctate 
leaves and with stipular spines. 

Flowers showy, in racemes ; fruit a flat bean. 

1. Twigs, petioles and pods glabrous or nearly so; flowers 
white. R. pseudoacacia. 

1. Twigs and petioles glandular; pods hispid; flowers 
pinkish, R. viscosa. 

1. Robinia pseudoacacia L. Common Locust. A large 
slender tree with very rough bark, of rapid growth. Wood 
very heavy, hard, strong, tough, valuable, and very durable in 
contact with the ground ; used for posts, railroad ties, wagon 
hubs, furniture, and in ship building. All parts of the plant 
very poisonous. It is troublesome from sprouting from the 
roots. Penn, and Ohio to Ga., Iowa, Kan., and Okla. 

2. Robinia viscosa Vent. Clammy Locust. A small 
tree with rough bark. Underground parts somewhat poisonous. 
Wood brown, the sap-wood yellow. Va. to Ga. Also escaped 
in Middle and Eastern States. 

Order, Celastraees. 

Rhamnaceae. Buckthorn Family, 

46. Rhamnus (Tourn.) L. Buckthorn. 

Shrubs or small trees with alternate, rarely opposite, sim- 
ple serrate or minutely serrulate leaves, and with berry-like 
drupes containing 2-4 stones. 

Flowers bisporangiate or diecious or imperfectly mono- 
sporangiate, small, in small axillary clusters. Twigs some- 
times ending in stout thorns. ^ 

1. Leaves acute, with 6-10 pairs of lateral veins; nutlets 
smooth ; umbels peduncled ; flowers bisporangiate. 
R. caroliniana. 

1. Leaves with 3 or 4 pairs of lateral veins, the basal pair 
prominent; nutlets of the fruit grooved; flowers 



‘>0 


Field Manual 


diecious or imperfectly monosporangiate. R. ca- 
thartica. 

1. Rhamnus caroliniana Walt. Carolina Buckthorn. 
A tall thornless shrub or small tree with a globose sweet drupe. 
In wet soil. Va. and Ohio to Kan., Fla., and Texas. 

2. Rhamnus cathartica L. Common Buckthorn. A 
shrub or small tree with black injurious fruit. Somewhat 
thorny and used for hedges. The fruit yields a dye and has 
powerful medicinal properties. Introduced from Europe. East- 
ern states. 

Cclastraceae. Stafftree Family. 

47. Euonymus (Tourn.) L. Wahoo. 

Shrubs or small trees with opposite, simple pinnately 
veined, serrate leaves, green twigs and central bundle-scars. 

Flowers regular, small ; fruit a 3-5-Iocular dehiscent cap- 
sule ; seeds enclosed in a red aril. 

1. Flowers purple ; cymes G-15 flowered ; winter buds 
long-pointed with long bud scales. E. atropurpu- 
rcm. 

1. Flowers greenish-yellow; cymes 3-7-flowered ; winter 
buds very short pointed with short bud scales. E. 
curopaeus. 

1. Euonymus atropurpureus Jacq. Wahoo. A high 
shrub or small tree with green, obtusely 4-angIed twigs. Leaves 
dark red and fruit very ornamental in autumn. Self-prunes 
small twigs by basal joints. Wood nearly white. Out. to 
Fla., Mont, and Okla. 

2. Euonymus europaeus L. Spindlctree. A shrub or 
small tree resembling the preceding. Self-prunes twigs. Cul- 
tivated from Europe. Escaped. N. Y., N. J. and Va. 

Ilicaccae. Holly Family. 

48. Ilex L. Holly. 

Shrubs or trees with alternate, not two-ranked, simple, 
pinnately-veined, serrate or lobed leaves which are sometimes 
evergreen; with watery sap; and with berry-like drupes con- 
taining several small stones. 



Trees of the Northern United States 


91 


Flowers small, in axillary clusters or solitary, mostly im- 
perfectly diccious. 

1. Leaves thick, persistent, evergreen, shiny. /. opaca. 

1. Leaves thin, deciduous, not spiny. 2. 

2. Leaves small, obovate or spatulate, crenate; nutlets of 

the fruit ribbed. /. decidua. 

2. Leaves large, ovate or lanceolate, sharply serrate, nut- 
lets ril)bed. I. montana. 

1. Ilex decidua Walt. Deciduous Holly. A shrub or 
small tree with light-gray, glabrous twigs and red drupes. 
Wood hard and white. In swamps and low ground. D. C. 
to Fla., Kan., and Texas. 

2. Ilex montana (T. & G.) Gr. Mountain Holly. A 
shrub or slender, erect tree growing in mountain woods. Drupes 
red. N. Y. to Ga., and Ala. 

3. Ilex opaca Ait. American Holly. A tree of slow 
growth with thick, glabrous, evergreen leaves and globose red 
or rarely yellow drupes. Twigs with leaves and fruit much 
used for Christmas decoration. Wood very white, fine-grained, 
hard, strong, tough, light in weight, and easily worked; used 
for cabinet-work and in turnery. Bird-lime is prepared from 
the middle bark. Jn moist soil. Should be much planted for 
ornament in suitable places. The leaves should be cut off 
when transplanted. Me. to Fla., Penn., Mo., and Texas. 

Ilex aquifdlium L. is the European Holly, sometimes cul- 
tivated. 

Order, Sapindales. 

Staphyleaceae. Bladdernut Family. 

49. Staphylea L. Bladdernut. 

Shrubs or small trees with opposite trifoliate serrate 
leaves. 

Stipules caducous ; flowers in axillary racemes or pani<?les, 
white bisporangiate, regular; capsule large and bladdery, tri- 
ocular. 

1. Staphylea trifolia L. American Bladdernut. A 
shrub or rarely small tree with smooth striped bark. Branch- 
ing a sympodial dichotomy. In moist soil. Quebec to Minn., 
S. Car. and Kan. 



92 


Field Manual 


Sapindaceae. Soapberry Family. 

50. Sapindus (Toiirn.) L. Soapberry. 

Trees or shrubs with alternate odd-pinnate leaves, with 
entire, inequilateral, acuminate leaflets, and with solid pith ; 
with axillary, exposed, superposed buds; and without stipular 
spines. 

Flowers imperfectly diecious; fruit a 1-3-seeded berry. 

1. Sapindus drummondii H. & A. Drummond Soap- 
berry. A tree with white flowers in dense terminal panicles 
and very saponaceous, globose berries. Wood hard, light yel- 
lowish brown; used in Texas for cotton baskets. Kan. and 
Mo. to La. and Ariz, 

51. Koelreuteria Laxm. 

Trees with alternate, odd-pinnate or hipinnate leaves with 
the leaflets toothed and usually more or less cut and lobed ; 
without prickles, stipules, or terminal buds, but with numerous 
scattered bundle-scars and large cylindrical pith. 

Flowers yellow diecious, in large terminal panicles ; fruit 
a trilocular bladdery capsule; outer bud-scales 2. 

1. Koelreuteria paniculata Laxm. Chinese Varnish- 
tree. A tree much planted for ornament. Reported as sponta- 
neous from seed in Indiana. 

Aesculaccae. Buckeye Family. 

52. Aesculus L. Buckeye, Horse-chestnut. 

Trees or shrubs with opposite palrnately compound leaves. 

Flowers imperfectly monosporangiate, zygomorphic, in ter- 
minal panicles, capsules leathery, containing large shining nut- 
like seeds. 

1. Flowers white, mottled with yellow and purple; leaf- 
lets abruptly acuminate ; winter buds gummy ; cap- 
sule spiny; bundle scars arranged in a curved line. 
A. hippocastanum. 

1. Flowers yellow or purplish; leaflets acuminate, more 

or less abrupt; winter buds not gummy; bundle 
scars arranged in 3 areas. 2. 

2. Capsule spiny, stamens exserted. 3. 



Trees op the Northern United States 


03 


2. Capsule glabrous ; stamens not longer than the petals, 

corolla yellow or purplish. A octandra. 

3. Leaflets acuminate, finely serrate, 5-7 ; a tree. A. 

glabra. 

3. Leaflets long-acuminate, unequally serrate, 7-9 ; a 

shrub-likc small tree. A. arguta. 

1. Aesculus hippocastanum L. liorse-chestnut. A 
large tree with very resinous, gummy winter buds. Autumn 
leaves orange. The seeds are ixiisonous and symptoms of 
poisoning have been produced from eating the green rind. The 
twigs contain Aesculin which is fluorescent in aqueous solution. 
Escaped from cultivation; native of Asia. 

2. Aesculus glabra Willd. Ohio Buckeye. A large 
tree with rough and fetid bark. Leaves, young shoots, and 
seeds poisonous to cattle. Wood light and hard to split; used 
for making artificial limbs, wooden- ware, and paper pulp. 
Penn, to Ala., Mich., Neb., and Okla. 

3. Aesculus arguta Buckl. Western Buckeye. A shrub- 
likc small tree with smooth bark. On flood plains. Neb. and 
Kan. to Texas. Reixirted from Iowa. 

4. Aesculus octandra Marsh. Yellow Buckeye. A 
large tree with brown scaly bark. Seeds poisonous. Wood 
light and hard to split ; used for making artificial limbs, wooden- 
ware and paper pulp. Aesculus octandra hybridia (DC.) 
Sarg. has purplish or pink flowers, leaflets pubescent beneath, 
and light brown bark. Penn, to Ga., Iowa and Texas. 

Aceraceac. Maple Family. 

53. Acer (Tourn.) L. Maple. 

Trees or shrubs with opposite leaves, with B-5 bundle scars 
in the narrow, contiguous leaf-scars, and with a terminal bud 
showing several pairs of visible scales. 

Sap watery or sometimes milky, often saccharine; fruit a 
2-winged samara. Usually diccious or imperfectly diecious. 

1. Leaves pinnate or trifoliate; twigs green, glaucous. 

A. negundo. 

1. Leaves simple. 2. 



Field Manual 


9A 

2. Leaves 'with very large teeth or lobes, the divisions not 
serrate or serrate-dentate. 3. 

2. Leaves with the large divisions or lobes serrate or 

serrate-dentate. 5. 

3. Leaves with stipules which arc often large and foli- 

aceous ; leaves green and pubescent beneath at least 
on the veins ; flowers corymbose, unfolding with the 
leaves; wings of fruit diverging a little less than a 
right angle. A. nigrum, 

3. Leaves without stipules. 4. 

4. Leaves with much milky sap in the petiole, glabrous, 

dark green above, lighter below, usually with 7 
prominent palmate veins ; flowers corymbose, un- 
folding with the leaves; wings of the fruit diverg- 
ing nearly in a straight line ; petals present ; winter 
buds rounded. A. platanoidcs. 

4, Leaves with watery or frothy sap, pale and nearly 

glabrous beneath, usually with 5 prominent palmate 
veins; flowers corymbose, unfolding with the leaves; 
wings of the fruit diverging a little less than a right 
angle; petals none; winter buds pointed. A. sac- 
charnm, 

5. Leaves very sharply and finely serrate, 3-lobed at the 

outer end, widest above the middle, the lobes ab- 
ruptly narrow-acuminate, brown pubescent below 
when young ; twdgs green, striix^d with darker lines ; 
flowers racemed, terminal, unfolding after the leaves. 
A. pennsyhanictwi. 

5. Leaves dentate-serrate or lobed, not abruptly narrow- 

acuminate ; twigs not striped. 6. 

6. Leaves broadly 3-5-lobed, the lobes rather regularly 

and continuously dentate-serrate or dentate-crenate ; 
flowers racemed, terminal, unfolding after the leaves. 

7. 

5. Leaves usually with 3-7 slender, long and pointed lobes, 
the lobes irregularly or interruptedly serrate or ser- 
rate-dentate ; flowers in dense sessile literal clus- 
ters, appearing before the leaves. 8. 

7. Leaves longer than wide, slightly 3-lobed at the outer 

end, usually only very slightly lobed at the lower 



Trees of the Northern Unitfj) States 


05 


end, not glaucous below; bark of twigs green or 
grayish; racemes erect; a shrub, rarely a small tree. 
A. spicatiim. 

7. Leaves as broad or broader than long, prominently 5- 

lobed, glabrous and dark green above, pubescent and 
light glaucous below, on long reddish petioles ; bark 
of twigs reddish-brown ; racemes drooping ; wings 
of fruit pubescent, moderately spreading; a large 
tree. A. pseudo-platanus. 

8. Leaves usually deeply 5-lobed, lobes slender, acute, 

white and glaucous beneath ; notches between the 
lobes often somewhat rounded ; fruiting pedicel short 
and stilT, 1-2 in. long; wings divergent; petals none. 
A, saccharinum. 

8. Leaves sharply 3-5 lobed, whitish glaucous beneath, 
notches acute ; fruiting pedicel long, slender and 
drooping, 2-4 in. long ; wings incurved ; ix^tals pres- 
ent. A. rubrum. 

1. Acer platano'idcs L. Norway Maple. A medium-sized 
tree with a broad rounded crown, with brown twigs and milky 
sap. Leaves sharply 5-7 lobed, very dark green above. Much 
cultivated. 

2. Acer pscudo-pldfanus L. Sycamore Maple. A fine tree 
with spreading branches. Leaves deeply 3-5 lobed. Self- 
prunes. Much cultivated. 

3. Acer pennsylvanicum L. Striped Maple. A small 
tree with smootliish green bark striped with darker lines. 
Leaves broadest above the middle, thin, glabrous above, 
slightly pubescent beneath when young, truncate or somewhat 
cordate at the base, 3-lobed near the apex. Wood white and 
soft. In rocky soil. N. S. to Lake Superior, and along the 
mountains to Ga. and Tenn. 

4. Acer spicatum Lam. Mountain Maple. A shrub or 
small tree, the bark green but not striped. Leaves 3-5~lobed, 
the lobes acute or acuminate, glabrous above, pubescent be- 
neath, at least when young. In damp rocky woods. Newf. to 
Man., south to N. Car., Tenn., Minn., and Iowa. 

5. Acer saccharum Marsh. Sugar Maple. A large 
tree with yellow or sometimes red leaves in autumn. Leaves 



Field Manual 


f^6 

cordate or truncate at the base, 3-7 lobed, the lobes, acuminate, 
irregularly sinuate, dark green above, pale and nearly glabrous 
beneath. Its sap is the main source of maple sugar and syrup. 
An average tree will yield 2-10 lbs. of sugar a season. A fine 
shade tree. The ashes give large quantities of potash. Wood 
heavy, hard, strong and lough ; used for fuel, interior finish, 
furniture, keels of boats and ships, implements and machinery, 
sucker rods, rims of bicycle wheels, piano action, school ap- 
paratus, large wood type, tool and broom handles, and wood 
carving. Newf. to Man., south to Fla. and Texas. 

6. Acer nigrum Mx. f. Black Maple. A large fine 
tree with rough blackish bark. Leaves cordate or truncate at 
the base, 3-7-lobed, the lobes broad and short, green on both 
sides, generally more or less pubescent beneath. It is equally 
valuable for the making of sugar. Wood much the same as 
in the Sugar Maple, and used for the same purposes. Ont. 
and Vt. to Ga., S. Dak., La., and Ark. 

7. Acer rubrum L. Red Maple. A tree with flaky 
or smoothish bark and reddish twigs. I^eaves sharply 3-o-lobed, 
the lobes irregularly dentate, acute or acuminate, cordate "at 
the base, green above, whitish beneath. Wood of considerable 
value when it shows a “curly grain.” Leaves crimson, scarlet 
or yellow in the autumn. Self-pruning like the following. 
Exists in many varieties. In swamps and low ground, also on 
moist hillsides. N. S. to Man., Fla., Neb., and Texas. 

8. Acer saccharinum L. Silver Maple. A large tree 
with flaky bark, the twigs often reddish, self-pruned by basal 
joints. Leaves deeply 5-lobed, the lobes rather narrow, acumi- 
nate, coarsely and irregularly dentate, truncate or slightly cor- 
date at the base, green above, silvery white and more or less 
pubescent beneath. A fine shade tree and much planted. Wood 
soft and white; used for furniture. Yields a small amount of 
sugar. Along streams. N. B. to Fla., Ont., S. Dak., Neb., 
and Okla. 

9. Acer negundo L. Boxelder. A small tree with 
spreading branches and glabrous, sometimes pubescent, green 
and glaucous twigs. Leaves 3-7 foliate, leaflets ovate or oval. 
The sap produces a slight amount of sugar. Wood light and 
of slight value. Along streams. Planted on the prairies for 



Trees of the Northern United States 97 

small groves and wind breaks. Maine to Man., Fla., Kan., 
and Mex. 

Anacardiaccac. Sumac Family. 

54. Rhus (Tourn.) L. Sumac. 

Small trees or shrubs with alternate pinnately compound 
leaves, with sticky milky or resinous sap, and pubescent drupes. 

Flowers in panicles, imperfectly bisporangiate, small ; sta- 
mens five, styles three ; drupe red. 

1. Petioles not completely covering the axillary buds; 
leallets entire; rachis of the leaf wing-margined; 
leaflets T-^U ; twigs and the red drupes pubescent. 
R. copallina. 

1. Petioles covering the axillary buds; leaflets serrate. 2. 

2. Leaves and twigs velvety-pubescent. R. hiria. 

2. Leaves and twigs glabrous, somewhat glaucous. A\ 
glabra. 

1. Rhus copallina L. Mountain Sumac. A shrub or 
small tree with a dense terminal panicle of small globose, 
crimson drupes, covered with short acid hairs. Leaves used 
for tanning purposes. Wood soft and light lirown. In dry 
soil. Me. and Ont. to Fla., Minn., Neb., and Texas. 

2. Rhus hirta (L.) Sudw. Staghorn Sumac. A small 
tree or shrub with red, pubescent drupes. Wood very soft and 
brittle. In dry or rocky soil. A good lemonade or “sumacade” 
is made by steeping the drupes and sweetening to taste. Leaves 
used for tanning. Wood soft, greenish-yellow. N. S. to Ga., 
Ont., S. Dak., Mo., and Iowa. 

3. Rhus glabra L. Smooth Sumac. A shrub or small 
tree with dense panicles of small crimson drupes covered with 
short acid hairs. Noted for its beautiful, brilliant, red-colored 
leaves in autumn. Leaves used for tanning. Common on hill- 
sides and bluffs. N. S. to Minn., Fla., Miss., and La. 

55. Toxicodendron (Tourn.) Mill. Poison Sumac. 

Small trees or shrubs, ours with alternate pinnate leaves 
with entire leaflets, with poisonous resinous sap, and with gla- 
brous or slightly pubescent drupes. 



98 


Field Manual 


Flowers small, in axillary panicles, imperfectly bisporan- 
giate; drupes gray or white. 

1. Toxicodendron vernix (L.) Ktz. Poison Sumac. A 
shrub or small tree, very poisonous to the touch. Drupes gray, 
glabrous in loose axillary panicles. In swamps and wet places. 
Wood soft, yellowish brown, poisonous. Maine to Fla., Ont., 
Minn., Mo., and La. 

56. Cotinus Adans. Smoketree. 

Small trees or shrubs with alternate, simple pinnately 
veined, entire, deciduous leaves and fragrant resinous sap. 

Flowers small, imperfectly bisporangiate, on a large ter- 
minal panicle ; stamens 5, styles 3, lateral ; drupe oblique, small, 
compressed ; buds clustered at the tip of the twig. 

1. Blade of the leaf slightly dccurrent on the petiole, thin, 
glabrous or slightly pubescent beneath. C. Amcri- 
canus. 

1. Leaves mostly rounded or obtuse at the base, coriace- 
ous more pubescent. C. coggygria. 

1. Cotinus americanus Nutt. American Smoketree. 
A small wide-branched tree. Wood soft, orange-yellow, yield- 
ing a rich dye. Mo. and Okla, to Tenn. and Ala. 

2. Cotinus coggygria Scop. European Smoketree. A 
small tree, native of Europe, frequently cultivated. 

Subclass, Amentiferae. 

Order, Platan ales. 

57. Hamamelis L. Witch hazel. 

Subfamily, Hamamelidatae. 

57. Ilamamdlis L. Witch-hazel. 

Shrubs or small trees with 2-ranked, simple, inequilateral, 
straight-veined leaves and stalked axillary buds. 

Flowers bisporangiate or imperfectly bisporangiate, in 
axillary clusters; fruit a bilocular, woody or cartilaginous, 
nut-like capsule. 

L Hamamelis virgini^na L. Witch-hazel, A shrub 
or small tree with 2-ranked leaves and stalked buds. Blooms 



Treks ok the Northern United States 


00 


in late autumn. Wood hard. In low ground and on banks. 
N. B. and N. S. to Minn., Mo., Fla., and Texas. 

Subfamily, Altingiatae. 

58. Liquidambar L. Sweet-gum. 

Trees with alternate, simple, palmately veined, fragrant, 
star-sha[)cd, serrate leaves and 5-anglcd pith. 

Sap resinous, aromatic ; flowers monecious, in heads, the 
stamnatc clusters racemose; capsules in a dense spiny glo- 
bular head. 

1. Liquidambar styraciflua L. Sweet-gum. A fine 
large tree with wide spreading branches, the twigs often covered 
with corky ridges. Leaves with a peculiar sweet fragrance 
when crushed. Autumn leaves red, yellow, and brown. Wood 
valuable, of medium weight, hard, not strong, tough, and of 
fine texture, reddish brown, difficult to season. Sometimes 
used as a substitute for black walnut. Used for furniture, 
veneer, wooden plates, plaques, baskets, hat blocks and wagon 
hubs. In low ground. Conn., N. Y. and Ohio to Fla., 111., 
Mo., and Mcx. 


Platanaceac^ Planetree Family. 

59. Platanus (Tourn.) L. Planetree. 

Large trees with alternate simple leaves having the base of 
the petiole cover the axillary bud and with complete stipular 
rings. 

Terminal bud self-pruned; flowers in spherical heads mone- 
cious, without perianth ; fruit in pendant spherical heads com- 
posed of numerous small nutlets. 

1. Bark exfoliating in large flakes; leaves usually deeply 
lobed, or the middle lobe about as long as broad ; 
fruit heads usually 2} or more on the peduncle. 2. 

1. Bark exfoliating in small plates; leaves 5-angled or 

slightly 8-5-lobed, the lobes broader than long; fruit 
heads solitary on the peduncle. P. occidentalis, 

2. Leaves deeply 5-7-lobcd, the sinuses reaching to or 

beyond the middle; fruit heads on the peduncle 2-6. 
P. orienialis. 



100 


Field Manual 


2. Leaves 3-5-lobed, the middle lobe of the leaf about as 
long as broad; fruit heads on the peduncle usually 2. 
P. accrifolia. 

1. Platanus occidentalis L. i5ycamore (Planetree). 
A very large tree, the largest in the northeastern United States, 
with whitish or green bark which peels oflf freely in thin 
plates ; the largest trunks usually hollow, sometimes as much 
as 42 feet in circumference. Autumn leaves brown. Wood 
rather hard, compact, coarse-grained, difficult to split, tough, 
and of a light-brown color ; used for tobacco boxes, cooperage, 
cabinet-work, and finishing hunber. Along the banks of streams 
and in moist ground, but grows well in ordinary mcsnphytic 
conditions. Me. to Ont. and Minn., Fla., Kan., and Texas. 

2. PJaiauus accrifolia Willd. London Planetree, A tall 
tree with erect, straight trunk and wide-spreading branches, 
the lower drooping. Young growth deiLscly brown-tomentose, 
the mature leaves glabrous or nearly so. Much planted as a 
street tree. 

3. Platanus orientalis L. Oriental Planetree. A large 
tree much like the Sycamore but usually with a comparatively 
short, massive trunk and a broad round crown. Leaves more 
cut and becoming smooth earlier. Occasionally planted. lYom 
Western Asia and Eastern Europe. 

Order, Urticales. 

Ulmaccae, Elm Family. 

60. Celtis (Tourn.) L. Hackberry. 

Trees or shrubs with 2- ranked, simple, leaves with two 
prominent lateral veins from the base and with interruptedly 
diaphragmed pith with cavities. 

Flowers in the axils of leaves, on short branches ; fruit 
an ovoid or globose drupe. 

1. Leaves sharply serrate ; smooth or scabrous above ; 
twigs glabrou.s, especially the fruiting ones, or pubes- 
cent. C. occidentalis, 

1. Leaves entire or few-toothed, small. C. laevigata. 

1. Celtis occidentMis L. Common Hackberry. A 

medium sized tree with rough bark. Commonly much distorted 



Trees of the Northern United States 


101 


with “witches brooms.” Drupe sweet and edible. Self-prunes 
the fruiting twigs in winter. Wood heavy, hard, strong, quite 
tough, greenish-white. In dry soil and on flood plains. Que- 
bec to Man., N. Car., Mo., Kan., and Okla. 

2. Celtis laevigata Willd. .Southern Hackberry, A 
medium-sized tree witli light gray, rough bark. Usually in dry 
soil. Va. to 111., Mo., Kan., Fla., and Texas. 

61, Planera Gmel. Planertrec. 

Trees with alternate, two-ranked, straight-veined, inequi- 
lateral, serrate leaves and with bark scaling off in plates. 

Trees similar to the elms but with a nut-like fruit and the 
flowers expanding with the leaves. 

1. Planera aquatica (Walt.) Gmel. Planertree. A 
small tree with nearly glabrous leaves growing in swamps and 
on wet banks. Wood compact, soft, weak, light brown. Ind. to 
Mo., Ky., N. Car., Fla., and Texas. 

62. Ulmus (Toiirii.) L. Elm. 

Trees with alternate, 2-ranked, pinnately straight- veined, 
inequilateral, doubly serrate leaves and sessile axillary buds. 

Flowers bisporangiate or imperfectly bisporangiate, in clus- 
ters or racemes; fruit a samara; trees of rapid growth. 

1. Leaves very rough above; twigs not corky- winged and 
not self-pruned, but large numbers of lateral buds 
cut off; inner bark sometimes mucilaginous. 2. 

1. Leaves smooth or sometimes somewhat rough above. 3. 

2. Inner bark very mucilaginous, buds rusty-downy, sa- 

mara much less than 1 in. long. U. fiilva. 

2. Inner bark not mucilaginous, buds not downy, samaras 

1 in. long, U. montana. 

3. None of the branches corky-winged ; twigs smooth, self- 

pruned by basal joints and by cleavage planes in the 
nodes of annual growth ; samara faces glabrous. 
U. aincricam. 

3. None of the branches with corky ridges; twigs gla- 
brous or nearly so, not self-pruned ; samara gla- 
brous or nearly so, deeply notched. U. cmnpestris, 

3. Some or all of the branches corky-winged, or twigs 



102 


Field Manual 


puberulent, self-pruned ; samara-faces pubescent. 4. 

4. Most of the branches with corky wing-like ridges ; 
twigs glabrous or nearly so ; leaves 1-3 in, long. 
U. data. 

4. Branches often with corky wing-like ridges ; twigs 
puberulent; leaves 2-5 in. long. U. thomasi. 

1. Ulmus americana L.. White Elm. A large tree of 
rapid growth, with the hark in thick, rough ridges ; much 
cultivated in cities and along roadsides. Trunks up to 33 
feet in circumference. Samara ovate-oval, its faces glabrous. 
Wood heavy, hard, flexible, and very tough ; used for wheel- 
hubs, saddle-trees, rough cooperage and furniture, in boat and 
ship building, in the construction of cars and wagons, and 
especially for barrel hoops. Common on bluffs and on the 
flood plains of rivers and creeks. Graceful in form and very 
suitable for cultivation. Newf. to Man., Fla., and Texas. 

2. Ulmus thomasi Sarg. Cork Elm. A large tree with 
puberulent young twigs, the branches or some of them with 
corky wings. Samara oval, its margins densely ciliate. Wood 
harder, stronger, and more durable than that of the White Elm. 
In rich soil. Quebec to Ont., Minn., Ky., Neb., and Mo. 

3. Ulmus al^ta Mx. Winged Elm. A small tree, 
branches usually with corky wing-like ridges; twigs glabrous 
or nearly so. Samara oblong, pubescent on the faces. Wood 
very compact; used for wheel hubs. In dry or moist soil. 
Va. to Fla., 111., Mo., and Texas. 

4. Ulmus campestris L. English Elm. A tree, rather 
pyramidal in shape, the twigs ascending, not drooping except 
in “weeping” forms. Samara not ciliate, nearly or quite gla- 
brous. A good timber tree. Cultivated, from Europe. 

5. Ulmus fulva Mx. Slippery Elm. A medium-sized 
tree with rough grayish-brown fragrant bark and rough-pubes- 
cent twigs. Samara oval-orbicular, pubescent over the seed. 
Inner bark mucilaginous and medicinal. Wood hard and strong 
but splitting easily when dry. Along streams, on flood plains 
and on hills. Quebec to N. Dak., Fla., and Texas. 

6. Ulmus montdna With. Scotch Elm. A large tree with 
spreading branches, or in some varieties with strictly upright 



Trees of the Northern United States 


m 


branches ; branchlets pubescent. Leaves rough above, pubes- 
cent beneath, doubly serrate, often somewhat 3-lobed at the 
apex. Many varieties fine for planting. From Europe. 

Ulmus pumila L. Chinese Elm. This tree is being ex- 
tensively planted in the prairie states. 

Moraceae. Mulberry Famly. 

63. Morus (Tourn.) L. Mulberry. 

Trees or shrubs with alternate, simple, 2- ranked leaves with 
two prominent side ribs from the base, with milky sap, and 
with glabrous or pubescent but not downy twigs. 

Flowers monosporangiate ; fruit aggregate, berry-like. 

1. Leaves scabrous above, pul>escent beneath. M, rubra, 

1. Leaves smooth and glabrous on both sides, or nearly so. 

M. alba. 

1. Morus rubra L. Red Mulberry. A small mone- 
cious or diecious tree with rough gray bark, separating in 
strips. Fruit dark purple-red, edible, delicious. Wood rather 
heavy, hard, strong, and rather tough ; very durable in contact 
with the ground, very valuable for posts ; used for farm im- 
plements, in cooperage, “acid wood,” and ship building. In 
rich soil. Vt. and Ont, to Mich., S. Dak., Fla., and Texas. 

2. Morus Mba L. White Mulberry. A small rapid- 
growing tree with rough light-gray bark and spreading branches. 
Fruit edible but usually rather insipid. Leaves used for feed- 
ing silk-worms. Wood suitable for posts. Although growing 
best in rich moist soil, it docs well in quite dry regions and 
should be much planted on the dry prairies, especially varieties 
with the better grade of berries. Introduced from the old 
world. Me. and Ont, to Fla., and Kan. 

Morus nigra L. Black Mulberry. A small tree with 
broadly cordate-ovate leaves, from Asia, and Europe, is some- 
times planted toward the south for its large purple or black 
fruit. 

64. Broussonetia L’Her. Paper-mulberry. 

Trees with alternate simple 2-ranked leaves having two 
prominent side-ribs from the base, with milky sap, and with 
downy twigs. 



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Flowers diecious, the staminate in ament-like spikes, the 
carpellate capitate; fruit a globular head of red drupes. 

1. Broussonetia papyrffera (L.) Vent. Paper-mul- 
berry. (Papyriiis.) A small, low-branching large-headed tree 
with dark scarlet fruit which is sweet but insipid. Native of 
eastern Asia. In Japan and China the bark is made into paper. 
Escaped from cultivation. N. Y. to Ga., and Mo. 

65. Madura Nutt.. Osage-orange. 

Small trees with alternate simple entire leaves, typical 
axillary thorns, and milky sap. 

Flowers decious, the staminate racemose, the carpellate 
capitate; fruit a large spherical, greenish or yellowish aggre- 
gate. 

1. Madura pomifera (Raf.) Schn. Osage-orange. 
{Toxylon.) A very thorny tree much planted for hedges. 
Leaves ovate to ovate-lanceolate, acuminate or taper-pointed. 
Wood very heavy, exceedingly hard and strong, but not tough, 
brownish-yellow ; valuable for fence posts and fire wood, also 
for wagon making. The thorns produce painful wounds. 
Horses acquire a strong liking for the young shoots and eat 
them in large quantities without apparent ill elTects. Mo. and 
Kan. to Texas. Escaped in Ohio and other eastern states. 

Order, Fag ales. 

Fagaceae. Beech Family. 

66. Quercus (Tourn.) L. Oak. 

Trees or shrubs with simple alternate leaves not 2- ranked ; 
with 5-angled pith : buds clustered at the tip of the twig ; 
and with scattered bundle-scars. 

Flowers monecious, the staminate in slender aments ; fruit 
A 1-seeded coriaceous nut (acorn) in an involucrate cup. 

1. Leaves not bristle-tipped; acorns maturing the first 
year. 2. 

1. Leaves with bristle-tips ; acorns maturing in the au- 

tumn of the second year. 11. 

2. Leaves crenate or dentate, not lobed. 3. 

2. Leaves pinnatifid or pinnately lobed. L 



Trees of the Northern United States 


105 


3. Fruits not on a peduncle, nearly sessile, teeth or shallow 
lobes of the leaves acute. 4. 

3. Fruits on a peduncle; teeth or shallow lobes of the 

leaves rounded. 5. 

4. Tall trees, leaves oblong, obovate or lanceolate. Q. 

miihlcnbergii. 

4. Shrub or low tree, leaves obovate or oval ; seed edible. 

Q. prinoidcs. 

5. Peduncle as long or shorter than the petioles ; leaves 

gray-tomentulose beneath. 6. 

5. Peduncle much longer than the petioles ; leaves white- 

tomentulose beneath. Q. bicolor. 

G. Teeth of the leaves acute or mucronulate ; bark white, 
flaky; seed sweet and edible; fruit short peduncled 
or sometimes nearly sessile. Q. prinus. 

6. Teeth of the leaves rounded; bark close; seed edible; 

petioles slender ; peduncles ecjualing or shorter than 
the petioles. Q. montana. 

7. Mature leaves pale, or glaucous and glabrous below. 8. 

7. Mature leaves pubescent or tomentose below, lyrate- 

pinnatifid. 9. 

8. Bark separating in thin scales, light gray or light 

brown ; cup shallow ; bracts thick and warty. Q. alba. 

8. Bark furtowed and ridged, not scaly, dark gray or dark 

brown ; cup hemispherical, with imbricated, ap- 
pressed scales ; cultivated in many varieties. Q. 
robur. 

9. Leaves pubescent beneath, oblong-obovate, usually 5- 

lobed, stellate-pubescent above ; upper scales of the 
cup not awned. Q. stellata. 

9. Leaves white-tomentulose beneath. 10. 

10. Leaves obovate or oblong, lyrate pinnatifid or deeply 
sinuate-lobed ; upper scales awned, forming a fringe 
around the acorn. Q. macrocarpa. 

10. Leaves obovate-oblong, deeply 5-9-lobed ; acorn often 

nearly enclosed in the cup, the up|>er scales not awned. 
Q. lyrata. 

11. Leaves entire, oblong, linear-oblong or lanceolate. 12. 

11. Leaves 3-5 lobed above the middle, or entire, obovate or 

spatulate in outline. 13. 



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Field Manual 


11. Leaves pinnatifid or pinnately lobed. 14. 

12. Leaves oblong or lanceolate, tomentulose beneath. Q, 

imbricaria. 

12. Leaves linear-oblong, green and glabrous on both sides. 

Q. phcllos. 

13. Leaves spatulate, glabrous on l)oth sides ; cup saucer- 

shaped, acorn globose-ovoid. Q. nigra. 

13. Leaves obovate-cuneate, brown-floccose beneath; cup 

deep, acorn ovoid. Q. nmrilandica. 

14. Leaves white or gray-tomentose below. 15. 

11. Leaves green on both sides. 17. 

15. Leaf-lobes lanceolate or linear-lanceolate, long; large 

trees. 16. 

15. Leaf-lobes triangular-ovate, short; shrubs or low trees. 

Q. ilicifolia. 

16. Leaves rounded or obtuse at the base, 3-5 lobed ; lobes 

linear or lanceolate, often falcate. Q. rubra. 

16. Leaves cuneate to truncate at the base, 5-11 lobed; lobes 

triangular. Q. pagoda. 

17, Leaves usually pubescent below; winter buds tomentose; 

cup turbinate or hemispherical ; inner bark orange. 
Q. zrelutina. 

17. Leaves glabrous with the exception of tufts of hairs in 

the axils of the veins below ; winter buds glabrous or 
minutely pubescent. 18. 

18. Cup of the acorn top-shaped or hemispheric. 19. 

18. Cup of the acorn saucer-shaped, much broader than 

deep. 20, 

19. Leaves dull, paler beneath; acorn ovoid, cup depressed- 

hemispheric, ^-1 in. wide. Q. borealis. 

19. Leaves shining above; cup of acorn top-shaped, about 
i in. wide, covering the nut. Q. ellipsoidalis. 

19. Leaves shining on both sides, lobed to near the mid-rib ; 

acorn ovoid; cup top-shaped, §-l in. wide. Q. cocci- 
nea. 

20. Leaves dull ; cup §-l in. broad ; acorn ovoid or elon- 

gated. Q. maxima. 

20. Leaves .shining abo\ne, paler beneath, with prominent 
axillary tufts of hairs; acorn ovoid, the cup deeply 
saucer-shaped. Q, schneckii. 



Trees of the Northern United States 


107 


20. Leaves shining, deeply pinnatified ; cup Li in. broad ; 
acorn subglobose or ovoid. Q. palustris. 

Chestnut Oaks. 

1. Quercus montina Willd. (Q. primis Du Roi not L.) 

Rock Chestnut Oak. A large tree with brown bark, ridged 
close or slightly flaky. Leaves oblong, oblong-lanceolate, or 
obovate, coarsely crenate, glabrous above, finely gray-tomen- 
tulose beneath, petioles slender ; cup hemispheric, i-li in. 
broad, peduncles equalling or shorter than the petioles; acorn 
ovoid, 2-3 times as high as the cup, seed edible but not very 
sweet. Self-prunes. Wood hard and strong; used in fencing 

and for railroad ties. Bark rich in tannin. In dry soil. Me. 

to Out., Ala., and Tenn. 

2. Quercus prinus L. {Q. michauxii Nutt). Cow Oak. 

A large tree with flaky white bark. Leaves obovate or broadly 
oblong, crenately toothed, the teeth often mucronulate, 4-8 in. 
long, cup depressed-hemispheric, short-peduncled, 1-U in. broad; 
acorns ovoid, about 3 times as high as the cup, sweet and 

edible. Wood valuable like the White Oak. In moist soil. 

Del. to Ind., Mo., Ark., Fla., and Texas. 

3. Quercus muhlenbergii Engelm. Chestnut Oak. A 
tree with close gray bark. Leaves oblong, lanceolate, or obo- 
vate, coarsely toothed with acute teeth, shining above, pale and 
gray-tomentulose beneath, 4-G in. long ; cup sessile or very 
short-peduncled, hemispheric; acorn ovoid about twice as high 
as the cup, sweet and edible. Self-prunes abundantly. Wood 
strong and durable, much like White Oak. Usually in dry 
soil, commonly on limestone ridges. Vt. and Ont. to Minn., 
Ala., Neb., and Texas. 

4. Quercus prinoides Willd. Scrub Chestnut Oan. A 
shrub or small tree with gray bark. Leaves obovate, coarsely 
toothed, bright green and shining above, gray-tomentulose be- 
neath, narrowed at the base; cup sessile, hemispheric, thin; 
acorn ovoid, 2-3 times as long as the cup; seed sweet and 
edible. Self-prunes. In dry sandy or rocky soil. Me. to 
Minn., Kan., Ala., and Texas. 

5. Quercus bicolor Willd. Swamp White Oak. A 
large tree with flaky gray bark. Leaves obovate, or oblong- 



108 


Field Manual 


obovate, coarsely toothed or sometimes lobed nearly to the 
middle, dull and glabrous above, densely white-tomcntulose be- 
neath ; peduncles of the hemisphere cup 2-5 times as long as 
the petioles ; acorn oblong ovoid, seed rather sweet. Self- 
prunes. Wood similar in value to that of the White Oak. In 
moist or swampy soil. Quebec to Minn., Ga., and Ark. 

White Oaks 

6. Quercus alba. L. White Oak. A large tree with a 
trunk up to 21 feet in circumference and with light-gray bark 
scaling off in thin plates. Leaves obovate, pinnatifid, lobes 
oblong, toothed or entire ; cup depressed-hemispheric, its bracts 
thick and warty, appressed ; acorn ovoid-oblong, 3-4 times as 
high as the cup, sweet and edible. Autumn leaves red and 
russet. Self-prunes extensively. Wood light-colored, hard and 
tough ; valuable for many purposes ; an ideal wood for rail- 
road ties ; used for poles, posts, and piling, for fuel and “acid 
wood,” for cooperage, furniture, interior finishing lumber, farm 
implements, wharves, ship building, and car and wagon work. 
The most valuable of the American oaks. Hybridizes with Q. 
macrocarpa, Q. stcUata- and Q. moniana. Me. to Ont., Minn., 
Fla., Kan., and Texas. 

7. Quercus rdhur L. English Oak. A large strong tree 
with stout more or less spreading branches forming a broad 
round-topped head; self-pruncs. Many forms are cultivated 
for ornament, including yellow-leaved and cut-leaved varieties, 
also forms with varied branches. Native of Europe. 

8. Quercus stellata Wang. Post Oak. A shrub or 
usually a small tree with a long tap root and with rough gray 
bark and valuable wood. Leaves broadly obovate, deeply 
lyrate-pinnatifid, glossy and stellate-pubescent above, brown- 
tomentulose beneath, 4-8 in. long ; cup hemispheric, nearly 
sessile; acorn ovoid, 2-3 times as long as the cup, very sweet. 
In dry soil. Mass, to Ohio, Mich., Iowa, Fla., and Texas. 

9. Quercus lyrata Walt. Overciip Oak. A large tree 
with gray or reddish bark in thin plates. Leaves obovate, 
lyrate-pinnatifid or lobed to beyond the middle, t>^ in, long, 
shining above, densely white-tomentulose beneath, cup de- 
pressed-globose, pcduncled, 1-li in. broad; aoorn depressed- 



Trees of the Northern United States 


10 .^ 


globose, nearly or quite immersed in the cup. Wood like in 
white oak. In swamps. N. J. to Ind., Mo., Fla., and Texas. 

10. Quercus macrocarpa Mx. Bur Oak. A large tree 
with bark in narrow rough ridges, slightly flaky, and with a 
long tap root. Leaves obovate or oblong-o])ovate, irregularly 
lobed, pinnatifid, or coarsely crenate shining above, grayish- 
white-tomcntulosc beneath, 4-8 in. long; cup short peduncled 
or sessile, lieinisphcric or subglobose, ^-1 in. broad, the tips 
of the bracts forming a fringe around the acorn ; acorn ovoid, 
1-2 times as high as the cup. Self-prunes abundantly. A very 
valuable tree with hard and tough wood resembling the White 
Oak. In rich soil or on river bluffs where it is sometimes 
small and shrubby. N. S. to Man., Mass., Ga., Wyo., Kan., 
and Texas. 

IVilloiv Oaks 

11. Quercus imbricaria Mx. Shingle Oak. A large 
stout tree, the leaves dying off but remaining on the tree until 
about April 1. Leaves oblong or lanceolate, entire, persist- 
ently gray-tomentulose beneath, 3-7 in. long ; cup hemispheric 
or turbinate, about h in. broad; acorn subglobose, bitter. Wood 
poor ; used for shingles and clapboards. Self-prunes twigs 
by means of basal joints. Q. Jeana Nutt, is a hybrid of this 
and Q. z»cliifma. Q. irdentata Englem. is a hybrid with Q. 
Hiarilandit'a. Also hybridizes with Q. palustris. Pa. to Mich., 
Neb., Ga., and Ark. 

12. Quercus phellos L. Willow Oak. A tree with 
slightly roughened, reddish-brown bark. Leaves narrowly-ob- 
long or oblong-lanceolate, entire, very short petioled ; cup 
saucer-shai)ed, nearly flat on the base ; acorn subglobose, bitter. 
Wood poor. In moist woods. Hybridizes with Q. ■ilidfolia 
and probably, with Q. maxima, producing the form known as 
Q. hetcrophylla. L. 1. to Fla., Ky., Mo., and Texas. 

Black Oaks 

13. Quercus nigra L. Black Water Oak. A tree of 
rapid growth with gray bark, rough in ridges. Leaves spatu- 
late or obovate, 1-3-lobed at the apex or some of them entire 
and rounded, short-petioled ; cup saucer-shaped, rounded at the 
base, about i in. wide ; acorn globose-ovoid, 2-3 times as high 



110 


Field Manual 


as the cup. Wood heavy, hard, and strong ; used for fuel. 
Usually along streams and swamps. Del. to Ky., Mo., Fla., 
and Texas. 

14. Quercus marilandica IMuench. Black-Jack (Oak). 
Usually a small shrubby tree ; bark nearly black with very 
rough ridges. Leaves obovate, 3-5 lobed toward the broad 
usually nearly truncate apex, cuneate below, the lobes short, 
stellate-pubescent above, brown-tomentose beneath when young, 
mature leaves glabrous above ; cup deep, about I in. broad ; 
acorn ovoid, 2-3 times as high as the cup. In dry sterile 
soil. Hybridizes with Q. phellos and Q. ilicijolia.. L. I. to 
Minn., Neb., Fla., and Texas. 

Red Oaks 

15. Quercus ilicifolia Wang. Bear Oak. A shrub or 
small tree, often forming thickets. Leaves mostly obovate, 2-5 
in. long, short petioled, grayish-white tomentulose beneath, 3-7- 
lobed, lobes triangular-ovate, acute; cup saucer-shaped, i-J in. 
broad, with a turbinate or rounded base ; acorn globose-ovoid, 
longer than the cup. In sandy or rocky soil. Me. to Pa., 
Del., and in mountains to N. C. and Ky. 

16. Quercus pagoda {Q, pagodaeiolia {R\\.) Asht) . 
Swamp Spanish Oak. A tree with spreading branches and 
dark gray, rough bark. Leaves oval or oblong, cuneate to 
truncate at the base, 8-12 in. long, deeply 5-11 lobed, persist- 
ently white-tomentulose beneath, lobes narrowly triangular, 
spreading or somewhat ascending, usually entire ; cup sessile, 
shallow, acorn globose, about one-half enclosed in the cup. 
In wet or moist soil. Mass, to Fla., III., Mo., and Ark. 

17. Quercus rubra L, {Q. tnloba Mx.). Spanish Red 
Oak. A tree growing in dry soil. Leaves glabrous above, 
gray-tomentulose beneath, deeply pinnatifid into 3-7 linear or 
lanceolate lobes ; cup saucer-shaped with a turbinate base, about 
i in. broad; acorn subglobose and depressed, about twice as 
high as the cup. Wood very hard and strong; used for 
cooperage. An important tanbark oak. N. J. to Fla., Ohio, 
Mo., and Texas. 

18. Quercus veliitina Lam. Quercitron Oak. A large 
tree of rapid growth with very dark brown bark, rough in 



Trees of the Northern United States 


111 


ridges, and bright orange inner bark. Leaves firm, sometimes 
lobed to beyond the middle, brown-pubescent or sometimes 
stellate-pubescent when young, glabrous and shining when ma- 
ture, the lobes broad, oblong or triangular-lanceolate ; cup 
hemispheric or top-shaped, commonly narrowed into a short 
stalk ; acorn ovoid, as long or longer than the cup. The inner 
bark (quercitron) yields a valuable dye; rich also in tannin. 
Wood hard, heavy, and strong but not tough. Sparingly self- 
prunes small twigs by means of basal joints. Ale. to Minn., 
Fla., Neb., and Texas. 

19. Quercus boreMis Mx. f. Gray Oak. A large tree 
with leaves like those of Q. luaxiina and acorns like those of 
Q, coccinea. Leaves 7-13 lobed to the middle or somewhat 
beyond; cup turbinate, peduncled; acorn ovoid, 1-2 times as 
long as the cup. Quebec to Out., N. Y., and Penn. 

20. Quercus coccinea Wang. Scarlet Oak. A tree 
with pale reddish or gray inner bark. Leaves deeply pinnatifid, 
glabrous, bright green above, paler beneath, 4-8 in. long; cup 
hemispheric or top shaped, acorn ovoid, about twice as long 
as the cup. Autumn leaves red. In dry soil Me. to Minn., 
Mo., and N. Car. 

21. Quercus ellipsoidalis E. J. Hill. Hill’s Oak. A 
tall tree with a large trunk diameter and smooth, close, gray 
bark. Leaves broadly obovate, deeply pinnatifid, with rounded 
sinuses, becoming glabrous and shining; acorn small; cup top- 
shaped, about i in. wide, covering i-i the ellipsoid nut. Per- 
haps a hybrid. In clayey soil. 111. to Mich., Iowa, and Alan. 

22. Quercus maxima (Marsh.) Ashe. (Q. rubra Du 
Ti^oi.) Common Red Oak. A large tree with dark gray bark, 
somewhat roughened. Leaves oval or somewhat obovate, 4-8 
in. long, dull green above, paler beneath, lobes triangular-lance- 
olate, tapering from a broad base to an acuminate apex; cup 
saucer-shaped, its base flat or slightly convex, i-1 in. broad; 
acorn ovoid, 2-4 times as long as the cup. Autumn leaves 
purplish red. Wood very coarse-grained, reddish in color, 
porous, and not very durable; used in carpentry, cooperage, 
and for clapboards. The most rapid grower of all the oaks. 
An important tree for tan-bark. Sprouts readily from stumps. 
N. S. to Ont., Minn., Fla., Kan., and Texas. 



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Field Manual 


23. Quercus schneckii Britt. Sclineck’s Oak. A 
very large tree with reddish-brown bark in broad ridges. Leaves 
obovate, shining above, paler beneath, with prominent tufts 
of hairs in the axils, deeply pinnatifid; acorn ovoid, cup deeply 
saucer-shaped. Wood hard, light red-brown. N. Car. to Ohio, 
Iowa., Mo., Fla., and Texas. 

24. Quercus palustris Mucnch. Pin Oak. A medium- 
sized tree w
…[truncated]