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FIELD MANUAL of TREES
Including Southern Canada and the Northern
United States to the Southern Boundary
of Virginia, Kentucky and Mis¬
souri, Westward to the
Limits of the Prairie
SECOND EDITION
By
JOHN H. SCHAFFNER
Professor of Botany and formerly Head of the Department
of Botany, Ohio State University
R. G. ADAMS & CO.
Columbus, Ohio
1922
PA Dept of Conservation and Natural Resources
Copyright, 1922
BY
John H. Schaffner
PREFACE.
This little manual represents a revision of the author’s
former “Trees of Ohio and Surrounding Territory,” and
attempts 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 identi¬
fication 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 used is essentially that of Britton and
Brown’s “Illustrated Flora of the Northern United States,
Canada and the British Possessions.” 2nd Edition, 1913. 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.
These names have been taken mainly from Sudworth’s “Check
List of the Forest Trees of the United States,” which on the
whole seems to be a very satisfactory basis for an appro¬
priate list. Synonyms will be found in the index.
Most 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 interest
in nature. When the tree has once been identified its
peculiarities should be learned by direct observation until its
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4
Field Manual
individuality becomes perfectly familiar. In winter one can
usually find dry leaves or fruit on the trees, which will make
it possible to tell most of the species at a time when many
think botanical study out of season.
In this second edition, a few typographical errors have
been corrected and a few slight changes have been made, but
the Manual remains essentially the same as the first edition
published in 1914.
J. H. S.
INTRODUCTION.
A tree may be defined as — a woody plant of any size
which produces naturally one main, erect stem with a definite
crown of branches. A shrub is a woody plant which produces
small irregular or slanting stems usually in tufts. In attempt¬
ing to separate “trees” from the larger “shrubs,” one must
necessarily be somewhat arbitrary as nature draws no definite
division line. There are also trees which have no crown of
branches, like the palms.
A tree has three main parts, the root system, the stem or
trunk, and the crown of branches. The root system is for
support in the soil and for taking up water and various
mineral substances. This is accomplished very largely by
delicate organs called root hairs developed near the root tips.
The root hairs are temporary structures developed from the
epidermis of the root (piliferous layer) near the tip and
dying off at the back as the root grows. Although largely
dependent on their environment the roots still have consider¬
able selective power in taking up the salts dissolved in the
soil water. The root system may have a main or tap-root
extending deep into the ground with smaller lateral roots ;
or the tap-root may be only slightly developed or entirely
absent, in which case a number of larger branch roots may
extend downward from the base of the trunk. The roots
which extend laterally near the surface sometimes run to a
great distance. Such roots are called tracing roots.
The trunk or bole is a supporting and conducting organ.
The water with dissolved mineral substances taken up by the
roots passes up through the young wood or xylem while the
food material from the young twigs and leaves passes up or
down through the phloem cells of the inner bark. There are
no real vessels for carrying food and water like the blood
vessels of animals, but the sap passes through by osmosis
from one cell to another or from one set of cells to another
as it frequently happens when some of the cross walls are
broken down in a vertical series of cells. The large cells in
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Field Manual
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 carri¬
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 Austrian pine. When the terminal bud has no pre¬
eminence 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. Excurrenf 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, 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
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 he
Tricks ok the Northern United States 7
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-
difference 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 a deposit of a chemical
substance called lignin.
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 andthe 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 in the cortex or even in the phloem of
the inner bark. In some plants the cork cambium originates
from the epidermis and in some from the deeper layers of
the cortex.
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
Field Manual
of a cleavage plane or separation layer through the base of
the petiole. They also prepare for winter by developing
elaborate winter buds. The function of the winter buds is
mainly to check evaporation from the delicate stem tips during
the periods of freezing and thawing.
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 elmi,
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 trees bear flowers and seeds. After arriving
at a certain age dependng on the species, the tips of some
twigs or the axillary buds will develop flowers. In the more
highly developed and typical flowers four sets of organs are
present ; the calyx composed of sepals, the corolla composed
of petals, the andrecium composed of stamens, and the gyne-
cium composed of carpels. The two essential sets of organs
in the flower are the stamens and the carpels. These may
both be in the same flower, when the flower is said to be
bisporangiate or in separate flowers, when the flower is mono-
sporangiate. If the staminate and carpellate flowers are on
one individual the plant is monecious, if on two distinct indi-
Trees of the Northern United States
9
viduals 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
inclosed in the ovulary. Commonly all the carpels of the
gynecium are grown together and in such cases a compound
ovulary is produced with one or more cavities.
Following a peculiar process known as the reduction
division which takes place in the cells inside of the micro¬
sporangium, a considerable number of microspores are de¬
veloped, 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 producing two kinds of nonsexual
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 sexual characters and dimorphism.
The microspores germinate and develop into the pollen grains
and the megaspores into the so-called embryo sacs, or minute,
parasitic, male and female gametophytes respectively, which
are the real sexual generation. After pollination 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
embryo sac. 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 fertilization. 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, endosperm 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 spo¬
rophyte and after sprouting develops 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 adaptation for seed distribution, so that the seed
with' its little embryonic tree inside may be carried away from
the parent plants to some other and perhaps more favorable
environment. Here, if conditions are proper, it sprouts and
10
Field Manual
begins its life as an independent individual. I'he whole
process of flower, seed, and fruit production is exceedingly
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, sub¬
ulate, 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
1 year. 3.
2. With feather-like dwarf branches, deciduous each
year, the linear leaves spreading into 2 ranks.
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. 6.
5. Leaf scar on the bark ; twigs without scales ; leaves
flat. Abies. (5).
li. Leaves flat, those on the upper side of the twig much
shorter than the lateral ones; trees. Tsuga. (4).
li. 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).
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Field Manual
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.'
Libocedrus. (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 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 quad¬
rangular, 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—
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
prominenf 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 vari¬
ously lobed. 25.
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
tapering at the base, acute or even heart-shaped.
Toxylon. (52).
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. (69).
15. Leaves evergreen, coriaceous, some on wood of the
previous season. 16.
15. No leaves on wood of the previous season. 17.
lii. Leaves green on both sides, thick, coriaceous, oblong
to oblanceolate, 5-10 in. long; winter buds very
scaly. Rhododendron. (66).
16. Leaves green on both sides, or glaucous beneath,
coriaceous, ‘2-5 in. long ; oval or oval-lanceolate,
winter buds naked. Kalmia. (67). '
16. 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
-bundles in base of petiole 3-7. 18.
17. Pith not both diaphragmed and solid, but sometimes
with lenticular cavities. 19.
18. Leaves 2-ranked ; bark with fetid odor ; vascular
bundles in base of petiole 5-7. Asimina. (14).
18. Leaves not 2-ranked; vascular bundles in base of
petiole 3. Nyssa. (81).
19. Leaves resin-dotted, waxy-dotted or punctate, oblong-
lanceolate, spatulate, or oblanceolate, short-pointed,
narrowed at the base. Myrica. (63).
19. Leaves not dotted nor punctate, 20.
20. Pith prominently'- 5-angled; leaves with deciduous
stipules and with bristle tips. Quercus. (56).
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. (79).
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
cavities, 24.
14
Field Manual
28. Leaves truncate or short-pointed at the base, usually
widest below the middle or somewhat oblong,
glabrous when mature; fruit a large pulpy berry,
very astringent when green. Diospyros. (70).
23. Leaves pointed.at the base, widest above the middle,
lower surface pubescent; fruit a nut-like drupe.
Symplocos. (71).
24. With prominent deciduous stipules; bark not resinous.
Cydonia. (24).
24. Without stipules; bark resinous, aromatic.
Cotinus. (44).
—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 quite regularly 2-ranked, that is with the third
leaf over the first. 30.
27. Pith 3-angled, buds stalked. Alnus. (60).
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 acumi¬
nate; buds clustered at the tip of the twig: nut in
a cup-like involucre of numerous scales.
Quercus. (56).
28. Leaves with sharply acuminate teeth; buds not clus¬
tered at the tip; nuts with a prickly or spiny
involucre. Castanea. (55).
29. LTsually with prominent and typical lateral thorns;
carpels of the pome bony. Crataegus. (26).
29. Without thorns but sometimes with thorn-like
stunted branches: leaves irregularly dentate, serrate
or crenate-dentate; sometimes lobed; pome fleshy
without grit cells: carpels papery or leathery.
Malus. (23).
29. Without thorns; leaves serrate or serrate-dentate;
pome berry-like, carpels not bony.
Amelanchier. (25).
Trees of the Northern United States
15
•BO. Leaves decidedly inequilateral at the base. 31.
30. Leaves not inequilateral or only very slightly so. 32.
31. Axillary buds prominently stalked; leaves repand-
dentate. Hamamelis. (45).
31. Buds sessile; leaves doubly serrate, bark not scaling
off in plates. Ulmus. (48).
31. Buds sessile; leaves serate, bark scaling off in plates
like in the Sycamore. Planera. (49).
0
32. Lateral veins ending in the large dentations or serra¬
tions 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 not 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. (54).
33. Leaves oblong-lanceolate, acuminate, with slender
often inwardly curved points on the serrations;
bark rough. Castanea. (55).
34. Lateral veins not ending in the serrations or teeth.
Amelanchier. (25).
34. Lateral veins ending in some of the serrations, teeth
or lobes. 35.
35. Bark smooth, the trunk and larger branches with
fluted or projecting ridges; leaves acute or acumi¬
nate, sharply doubly serrate; nuts small, in a large-
bracted catkin. Carpinus. (57).
35. Trunk and larger branches not with fluted or project¬
ing 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. (59).
36. Bark of trunk scaly, fine furrowed; twigs glandular-
bristly; carpellate catkin in fruit appearing like
that of the hop. Ostrya. (58).
36. Bark scaling off in plates like in the Sycamore; fruit,
coriaceous, nut-like. Planera. (49).
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. (69).
38. Bark not in papery or leathery sheets; leaves not
doubly serrate, the lateral veins not ending directly
in the serrations or teeth. Amelanchier. (25).
39. Leaves not with spines. 40.
39. Leaves evergreen, with spine-tipped lobes. Ilex. (36).
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. (81).
40. Pith solid, without diaphragms. 42.
41. Leaves oval or obovate, serrate or denticulate,
abruptly acuminate, wedge-shaped at the base, more
or less stellate pubescent beneath; bark of twigs
peeling off in slender shreds; fruit 4-winged.
Halesia. (72).
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 pubescent, not stellate; fruit a nut-like drupe.
Symplocos. (71).
42. Leaves with peltate scales, or resin-dotted, oblanceo-
late or wedge-lanceolate. Myrica. (63).
12. 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; bundle
scars or vascular bundles in base of petiole. 3.
Salix. (65).
44. Pith decidedly 5-angled. 45.
14. Pith cylindrical or nearly so. 46.
45. Bundle scars 3; leaves with gland-tipped teeth, usually
broad-based, usually with 2 prominent glands at
the base of the blade. Populus. (64).
Trees of the Northern United States 17
45. Bundle scars several, scattered; leaves without
glands; buds clustered at the tip of the twig.
Quercus. (56).
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. (68).
47. With typical lateral thorns; fruit a drupe-like pome
with bony ripe carpels. Crataegus. (26).
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 velyety
drupe. Amygdalus. (28).
46. Glands various; twigs not red and green, some with
cleavage planes in basal joints; terminal bud present
or absent, fruit a smooth drupe. Prunus. (27).
50. Axillary buds usually superposed; leaves lanceolate or
oblong-lanceolate, tapering towards the short
petiole; fruit a berry-like drupe. Ilex. (36).
*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 prominent and nearly parallel and curving
upward at the margin of the leaf: fruit a berry-like
drupe. Rhamnus. (34).
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. (22).
52. Leaves irregularly dentate or serrate, or more or less
lobed; pome without grit cells. Malus. (23).
18
Field Manual
—53—
■53. Base of petiole covering the axillary bud; twigs with
stipular rings. Platanus. (47).
53. Axillary buds usually evident; twigs without stipular
rings. 54.
54. Leaves 2-ranked. 55.
54. Leaves not 2-ranked. 60.
55. Leaves entire, round-heart-shaped. Cercis. (29).
55. Leaves serrate, dentate, or lobed. 56.
56. Pith usually in transverse plates; leaves ovate-lance¬
olate, inequilateral, taper-pointed. Celtis. (50).
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; leaver
pubescent or glabrous beneath. Morus. (51).
58. Twigs grayish-green, downy; leaves tomentose be¬
neath. Papyrius. (53).
59. Leaves- not inequilateral; vascular bundles in base of
petiole 3. Betula. (59).
•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. (46).
60. Leaves' entire or three-lobed, bark spicy-aromatic; in¬
ternodes 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. (64).
61. Pith cylindrical or nearly so; usually with prominent
typical thorns. Crataegeus. (26) .
— 62 —
62. Pith diaphragmed, with cavities; large trees with pin¬
nate leaves. Juglans. (62).
62. Pith not diaphragmed. 63.
63. Leaves trifoliate, odd-pinnate or odd-bipinnate. 64.
Trees of the Northern United States
19
63. Leaves evenly pinnate or bipinnate; axillary buds
superposed. 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 trifloliate, 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; some times 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. (42).
68. Leaves serrate; bipinnate, petioles and stems prickly.
Aralia. (78).
69. Leaflets mucronate, usually obtuse; with stipular
spines; base of petiole solid. Robinia. (33).
69. Leaflets abruptly acute; without stipular spines; base
of petiole covering the buds like a cap.
Cladrastis. (32).
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. (38).
71. Leaflets not inequilateral or only slightly so, not
slender falcate, the rachis winged; twigs pubescent.
Rhus. (42).
71. Leaflets not inequilateral or only slightly so; not
slender falcate; rachis not winged; twigs glabrous.
Toxicodendron. (43).
20
Field Manual
i 2. Pith 5-angled; stipules none, base of petiole with nu¬
merous vascular bundles, scattered or in 3 areas.
Hicoria. (61).
72. Pith not 5-angled; stipules none; leaflets more or less
lobed; vascular bundles in base of petiole scattered;
terminal bud absent. Koelreuteria, (39).
(2. Pith cylindrical or nearly so; leaves with stipules;
vascular bundles in base of petiole 3-5. Sorbus. (21).
73. Pith small; base of petiole covering the axillary buds;
usually with prominent thorns. Gleditsia. (30).
73. Pith very large, base of petiole not covering the
— axillary buds; without thorns. Gymnocladus. (31)
74. Leaves simple. 78.
74. Leaves compound. 75.
75. Leaves digitate with 5 or more leaflets. Aesculus. (40).
75. Leaves trifoliate or pinnate. 76.
76. Base of petiole covering the axillary buds; leaflets
dentate, lobed, or nearly entire. Acer. (41).
76. Base of petiole not covering the axillary buds. 77.
77. Leaves trifoliate; bark with strong odor; terminal
bud self-pruned. Staphylea. (37).
77. Leaflets 5-13; terminal bud present. Fraxinusl (74).
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-lobed with entire
margin. 80.
79. Leaves serrate, crenate, dentate or variously lobed. 81.
80. Pith diaphragmed, or with large cavities; petioles
usually hollow; axillary buds superposed.
Paulownia. (76).
80. Pith and petioles solid; axillary buds not superposed;
under side of leaves with glands in the axils of the
larger veins. Catalpa. (77).
81. Leaves more or less lobed; fruit a 2-winged samara.
Acer. (41).
81. Leaves not lobed; fruit a drupe. Rharanus. (34).
82. Leaves serrate, dentate, crenate, or variously lobed. 83.
Trees of the Northern United States
21
82. Leaves entire. 85.
83. Bark of ripe twigs green, bundle scar or vascular
bundle in base of petiole 1; pith rhombic.
Euonymus. (35).
83. Bark of ripe twigs gray, brown, or red; pith cylin¬
drical or nearly so. 84.
84. Axillary buds sometimes superposed; leaves finely
denticulate; twigs light brown, sometimes thorny;
drupe narrowly oblong. Forestiera. (75).
84. Axillary buds not superposed; twigs not 4-angled,
brown; flowers epigynous; fruit a fleshy drupe;
vascular bundles in the base of the petiole 3.
Viburnum. (83).
84. Axillary buds not superposed; leaves serrate with
stipules, small; bundle scar central; twigs brown,
sometimes with thorns; slmib-like trees with
drupe-like berries. Rhamnus. (34).
85. Leaves coriaceous, evergreen, hence on wood of the
previous season. Kalmia. (67).
85. Leaves deciduous each year. 86.
86. Leaves with the 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; inflo¬
rescence cymose. Cornus. (79).
87. Axillary buds minute, hidden by the petiole base;
flowers in involucrate heads. Cynoxylon. (80).
88. Stipules none; fruit an oblong drupe.
Chionanthus. (73).
88. Stipules present; fruit dry, in a head.
Cephalanthus. (82).
KEY TO THE GENERA OF TREES IN THE
WINTER CONDITION. ’
Based mainly on twig and stem characters. The num¬
ber following 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.
■'!. 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. 6.
3. I. eaves 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 iti 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 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-(>.
the two upper fertile, not peltate. Libocedrus. (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 of the carpellate cone peltate.
Chamaecyparis. (10).
(22)
Trees 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 quad¬
rangular, the subulate leaves spreading; one or both
types of leaves on a plant; carpellate cone develop¬
ing into a bluish-black, berry-like fruit.
Juniperus. (11).
8. Leaves with spine-tipped lobes or teeth. Ilex. (36).
8. Leaves without spines. 9.
9. Leaves pubescent at least below, lanceolate, mucro-
nate, not evergreen; buds clustered at the tip of the
twig; trees_ with 5-angled pith. Quercus. (56).
9. Leaves glabrous below; pith not 5-angled. 10.
10. Leaves green on both sides, thick, coriaceous, oblong
to oblanceolate, 5-10 in. long; winter buds very
scaly. Rhododendron. (66).
10 Leaves green on both sides or glaucous beneath,
coriaceous, 2-5 in. long, oval to oval-lanceolate;
winter buds naked; erect shrubs. Kalmia. (67).
10. Leaves bright green above, paler beneath, coriaceous,
4-5 in. long, pointed at both ends; bark aromatic.
Persea. (15).
—11—
11. Twigs with thick wart-like dwarf branches; gymnos-
perms. 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 branche_s,
some usually remaining in winter; foliage leaves
spreading into two ranks; 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.
24
Field Manual
15. Twigs without complete stipular rings. 18.
16. Leaf scar surrounding the axillary bud, terminal bud
self-pruned; wood with prominent medullary rays.
Plantanus. (47).
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; pith
with or without diaphragms; leaf scars LT- shaped,
oval, or circular; bark usually aromatic.
Magnolia. (12)
18. With thorns, prickles, or spines; or with spur-like
brandies 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
liearly around the stem, with about 20 bundle scar>;
pith large. Aralia. (78).
20. Leaf scar covering the two or more superposed
axillary buds. Robinia. (33).
20. Leaf scar below the axillary buds; buds reddish. -
pubescent. Zanthoxylum. (17).
21. With thorns beside the axillary buds; normally one
for each leaf axil, becoming gradually smaller
toward the tip of the twig, terminal bud absent.
Toxylon. (52).
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. (26).
Trees of the Northern United States
25
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. Gleditsia. (30).
22. Not with three distinct bundle scars. 2-3.
22. With three bundle scars. 24.
23. Buds and twigs glabrous or nearly so; with few
thorns. Rhamnus. (34).
23. Buds and sometimes twigs pubescent or downy;
thorns prominent. Bumelia. (69).
24. Terminal bud self-pruned; twigs some shade of black,
brown, or reddish. Prunus. (27).
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. (22).
25. Buds downy or pubescent, twigs usually pubescent, if
glabrous then dark reddish-brown; trees with
rounded crowns and spreading branches.
Malus. (23).
—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. Bundle scar 1; visible bud scales 2; twigs brown:
pith sometimes with cavities. Diospyros. (70).
27. Bundle scars 3. 32.
27. Bundle scars more than 3, usually scattered. 28.
28. Pith diaphragmed, solid; bundle scars 5-7; bark with
fetid odor; terminal bud elongated, naked, silky;
stipular scars none. Asimina. (14).
28. Pith not diaphragmed; bark not with fetid odor. 29.
29. With very prominent medullary rays. 30.
29. Medullary rays inconspicuous. 31.
30. Winter buds usually long-pointed, with several to
numerous dry scales. Fagus. (54).
30. Winter buds rather fleshy, usually with 1-3 visible
scales. Tilia. (29).
PA Dept oi Conservation and Natural Resources
Field Manual
Pith 5-angled, twigs glabrous or somewhat pubes¬
cent, reddish or yellowish-brown. Castanea. (50).
Pith cylindrical; visible bud scales more than 3;
twigs glabrous or -pubescent but not' downy.
Morus. (51).
Pith cylindrical; visible bud scales 1-3, twigs downy,
grayish-green, bark very fibrous. Papyrius. (53).
Pith interruptedly diaphragmed, with cavities, small,
greenish-white. Celtis. (50).
Pith solid. 33.
Terminal bud naked, elongated, tomentose; buds'
prominently stalked, light gray; twigs zigzag.
Hamamelis. (45).
Terminal bud absent, the twig showing a terminal
self-pruning scar at the morphological tip; or if
present then with scales; buds not stalked. 34.
Terminal bud present, long pointed; leaf scar narrow
contracted between the bundle scars.
Amelanchier. (25).
Terminal bud absent, or if present then the leaf scar
oval or semicircular. 35.
Twigs dark reddish-brown, speckled, often zigzag;
buds reddish-violet, often superposed or clustered;
leaf scars not oblique but below the lateral bud.
Cercis. (29).
Twigs dark brown, not speckled; buds not superposed;
leaf scars oblique. 36.
Bark smooth, trunk and large branches with peculiar
fluted or projecting ridges; bud scales brown,
finely pubescent; staminate catkins in the bud in
winter. Carpinus. (57).
Trunk not with fluted or projecting ridges. 37.
Bark of trunk scaling off like in the Sycamore’; twigs
very slender; no catkins. Planera. (49).
Bark in rough ridges; no catkins; twigs and buds in
most cases pubescent; some species with character¬
istic transverse self-pruning scars on the twigs,
others with corky ridges. Ulmus. (48).
Trees of the Northern United States
27
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. Ostrya. (58).
:!7. Bark of trunk and larger branches separating into
papery or leathery sheets; catkins in winter.
Betula. (59).
—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
superposed. 46.
39. Pith diaphragmed, with air cavities. 40.
39. Pith diaphragmed but solid; bundle scars 3; stipular
scars none, Nyssa. (81).
39. Pith not diaphragmed, solid. 41.
•lit. Pith large, brown; twigs thick, with large leaf scars
and 3 prominent bundle scars. Juglans. (62).
4D. Pith rather small, white or greenish; leaf scars semi¬
circular; outer bud scales about 2. Halesia. (72).
41. Buds partly sunken, hardly projecting beyond the sur¬
face; 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. (31).
42. Leaf scar surrounding the axillary buds, quadran¬
gular U-shaped; bark with pungent odor; pith
white. Ptelea. (18).
42. Peaf scar covering the axillary buds; pith small; twigs
brown, polished, often zigzag. Gleditsia. (30).
43. Pith cylindrical or nearly so. 44.
43. Pith more or less 5-angled, yellowish or brownish;
terminal bud large; bundle scars scattered; trees
with tough twigs. Hicoria. (61).
28
Field Manual
44.
44.
4-5.
45.
Leaf scar surrounding the hairy axillary buds; bundle
scars 5-9; terminal bud self-pruned.
Cladrastis. (32).
Leaf scar not surrounding the axillary buds. 45.
Bundle scars 3; buds spherical, bark light gray; leaf
scars heart-shaped; stipular scars none.
Sapindus. (38).
Bundle scar usually 1; buds rounded or somewhat
pointed; stipular scars or minute stipules present.
Ilex. (36).
46—
46. Terminal and lateral buds stalked; pith 3-angled; both
staminate and carpellate catkins present all winter.
Alnus. (60).
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. (42).
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. 50.
49. Stipular scars and stipules none. 51.
50. Terminal bud absent; bud scales dark brown or
black. Rhamnus. (34).
50. Terminal bud present; stipules minute, usually per¬
sistent. Ilex. (36).
51. Terminal bud present. 52.
51. Terminal bud absent. 53.
52. Pith diaphragmed, with cavities; bark reddish; outer
bud scales several, short. Symplocos. (71).
52. Pith not diaphragmed; bark green, very spicy aro¬
matic; internodes very unequal. Sassafras. (16).
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. (68).
Trees of the Northern United States
29
53. With 2 visible scales in the triangular flattened bud;
pith sometimes with cavities; twigs pubescent, zig¬
zag at the tip. Diospyros. (70).
—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
present; bundle scars 3; pith small. Salix. (65).
55. Pith diaphragmed but solid; bundle scars 3; no stip¬
ular scars. Nyssa. (81).
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. (56).
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; ter¬
minal bud present or absent; stipular scars promi¬
nent. Castanea. (55).
59. Terminal bud large with 4 or more visible scales, hairy
or peltate pubescent; lateral buds usually super¬
posed; twigs tough. Hicoria. (61).
60. Without stipular or self-pruning scars; crushed buds
fragrant, aromatic, not resinous, glabrous.
Liquidambar. (46).
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 pubes¬
cent or tomentose. Populus. (64).
61. Pith very large, light brown, bark not resinous, ill-
smelling; 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-
resinous. 62.
30
Field Manual
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. (44).
63. Buds not clustered at the tip; bark often very poison¬
ous to the touch; leaf scar partly surrounding the
bud; small trees or shrubs. Toxicodendron. (43).
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. (63).
66. Buds not clustered at the tip; twigs not glandular;
bundle scars 3. Prunus. (27).
66. Buds not clustered at the tip; twigs not glandular;
bundle scars numerous; outer bud scales 2.
Koelreuteria. (39).
67. Buds and twigs very downy, twigs dark brown or
black. Cydonia. (24).
67. Buds downy or pubescent; twigs glabrous or pubes¬
cent, gray or brown. Rhamnus. (34).
68. Twigs green or yellowish-green, glabrous; internodes
very unequal; lateral buds minute; small trees.
Comus. (79).
68. Twigs normally red above and green beneath,
glabrous; bark very bitter; some axils with 2 or 3
hairy buds of nearly equal size; trees.
Amygdalus. (28).
68. 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. (21)
69. Bundle scars 3. 70.
70. Buds rounded at the apex, often clustered at the tip
of the twig; twigs glandular dotted. Myrica. ('63').
Trees of the Northern United States 31
70. Buds rounded at the apex; scales thick; twigs often
zigzag; plant usually with some thorns, pot gland¬
ular dotted. Crataegus. (26).
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. (27).
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. (22).
71. Buds downy or strongly pubescent; twigs strongly
pubescent or if glabrous then dark reddish-brown;
trees ‘with rounded or spreading crowns.
Malus. (23).
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. (34).
—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 elipse or ring; buds
small and flat or superposed, pith large. 73.
73. Pith with cavities or more or less diaphragmed; axil¬
lary buds superposed. Paulownia. (76).
73. Pith solid; axillary buds small and flat, not super¬
posed, leaf scars often in threes. Catalpa. (77).
74. Twigs very green, more or less 4-angled; pith dia¬
mond-shaped or rhomboidal. Euonymus. (35).
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. (34).
75. Terminal bud present unless the twig is fruiting. 76.
Field Manual
32
Hi. Axillary buds often superposed; twigs often with
thorns; leaf scars small. Forestiera. (75).
76. Axillary buds not superposed; no thorns on the twigs;
leaf scars rather large. 77.
77. Twigs and buds pubescent; lateral buds cylindrical or
hemispherical; bud scales dry; leaf scar concave, on
the short petiole base; lenticels large and con¬
spicuous; fruit a drupe. Chionanthus. (73).
77. Buds rough or pubescent; twigs glabrous or pubes¬
cent, sometimes 4-angled; lateral buds somewhat
flattened, obtuse; bud scales rather dry; leaf scar
close to the bark; lenticels not large; fruit a
samara. Fraxinus. (74).
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. (37).
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. (40).
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.
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. (41).
81. Axillary buds usually minute and undeveloped ex¬
cept at the base of the peduncle which is self-
pruned; twigs green or reddish-green, glabrous or
nearly so. Cynoxylon. (80).
81. Axillary buds normally well developed and prominent;
twigs often very pubescent. Cornus. (79).
GENERAL KEY TO THE FAMILIES AND GENERA.
Based 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 di¬
rectly on the micropyle of the ovule which is
without a pollen-chamber; trees or shrubs; ours
usually evergreen 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. Leaves not fanshaped and dichotomously veined, but
needle-shaped, narrowly linear, subulate or scale¬
like. 3.
3. Leaf buds naked; carpels few, spiral; leaves on
feather-like dwarf branches which are deciduous.
Taxodiaceae.
✓
a. Taxodium. (2).
3. Leaf-buds naked; carpels few, opposite, sometimes
forming a black or blue berry-like fruit; leaves
opposite or whorled, rarely scattered, persistent
JUNIPERACEAE.
a. Carpellate cones oblong, the scales not peltate, b.
a. Carpellate cones globose or nearly so, the scales
peltate, or forming a bluish berry-like fruit, c.
b. Cone scales 6-10, the 4 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).
(33)
Field Manual
34
c. Cone becoming blue and fleshy; twigs not flat¬
tened; leaves or some of them often subulate.
Juniperus. (11).
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 scar on the bark; twigs without scales;
leaves usually flat; carpellate cones erect.
Abies. (5).
c. Leaves more or less 4-sided, spreading in all di¬
rections; 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. Monocotylae,
4. Leaves usually netted-veined; parts of the flower
more commonly in fives (pentamerous) or fours
(tetramerous) ; cotyledons usually 2, vasculai
bundles usually in a circle around a central pith,
forming annual rings of growth in perennial stems,
with bark on the outside. 5.
Trees of the Northern United States
35
5. DICOTYLAE.
5. Perinath none or of similar segments or divided into
calyx and corolla; corolla when present chori-
petalous (petals distinct), sepals, petals and stamens
sometimes on a disk or hypanthium. 6.
5. Perinath composed of calyx and corolla, calyx may be
minute or suppressed; corolla sympetalous (petals
more or less united). 39.
0. Calyx and corolla both present, calyx may be minute.
7.
I). 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 hypan¬
thium. 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 alter¬
nate with them. 12.
8. Stamens of the same number as the petals and op¬
posite 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 sim¬
ple leaves. Rhamnaceae.
a. Rhamnus. (34).
9. Carpels 1 or more, united, but styles and stigmas
may be several. 10.
9. Carpels more than 1, district; 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 cone-like
fruit; trees; sepals and petals in threes; twigs
with stipular rings. M ag noli acf. a e.
Field Manual
36*
a. Anthers introrse: leaves not truncate.
Magnolia. (12).
a. Anthers extrorse; leaves truncate.
Liriodendron. (13).
10. 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).
a. Young ovulary and drupe glabrous. Prunus. (27).
a. Young ovulary and drupe velvety-pubescent.
Amygdalus. (28).
11. Flower cluster subtended by a large, membranous
bract; calyx deciduous; leaves alternate, 2-ranked;
sap mucilaginous. Tiliaceae.
a. Tilia. (20).
11. Flowers not subtended by a membranous bract; leaves
alternate with deciduous stipules; sepals per¬
sistent. Rosaceae. (Malatae).
See 24 below.
12. Ovulary only 1, carpels 1 to many, united. 15.
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-
MELIDACEAE.
a. Ovules 1 in each cavity; leaves inequilateral, not
star-shaped. Hamamelis. (45).
a. Ovules several in each cavity, fruit globular,
spiny. Liquidambar. (46).
14. Leaves punctuate with pellucid dots, alternate.
Rutaceae.
a. Zanthoxylum. (17).
14. Leaves large, pinnate, alternate, not punctuate but with
disc-like glands under the teeth or lobes. Sima-
rubaceae.
a. Ailanthus. (10).
15. Carpel 1, ovulary with 1 parietal placenta; leaves
alternate, usually with stipules, usually compound
Fabaceae.
Trees of the Northern United States
37
A. Upper petal inclosed by the lateral ones in the
bud; leaves simple or compound mostly with
stipules. Cassiatae.
a. Leaves simple, flowers bisporangiate.
Cercis. (29).
a. Leaves compound, flowers diecious or imper¬
fectly diecious. b.
b. Stamens 3-5; pith small; usually with
thorns. Gleditsia. (30).
b. Stamens 10; pith large, chocolate-colored;
without thorns. Gyrnnocladus. (31).
B. Upper petal inclosing the lateral ones in the bud;
leaves compound (sometimes with 1 leaflet)
with stipule's. Fabatae.
a. Without stipular spines; leaflets large, 3-6 in.
long; base of petiole covering the axillary
buds like a cap. Cladrastis. (32).
a. With stipular spines; leaflets small, 1-2 in.
long; base of petiole not covering the
axillary buds like a cap, but solid.
Robinia. (33).
15. Carpels more than 1 as shown by the compound
ovulary, 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. Anafardiaceae.
a. Leaves compound; style terminal, b.
a. Leaves simple: style lateral. Cotinus. (44)
b. Petiole base covering the axillary buds, or if not
then the rachis wing-margined; not poisonous.
Rhus. (42).
b. Petiole base not completely covering the axillary
buds, the rachis not wing-margined; poisonous
to the touch; glabrous; leaflets entire.
Toxicodendron. (43).
17. Flowers regular or nearly so. 18.
17. Flowers irregular; shrubs or trees with opposite
digitate leaves; ovulary 3-locular. Aesfueaceae.
38
Field Manual
a. Aesculus. (40).
17. Flowers irregular in the number of the several floral
sets; leaves pinnate or bipinnate, alternate; ovu-
lary 3-locular. Sapindaceae.
a. Koelreuteria. (39).
18. Stamens neither just as many nor twice as many as
the petals. 19.
18. Stamens just as many or twice as many as the
petals. 20.
IS. Stamens distinct and fewer than the 4 petals; trees
or shrubs with opposite pinnate or simple leaves.
Oleaceae.
a. Flowers diecious, from catkin-like scaly buds.
Fcrestiera. (To).
a. Flowers bisporangiate', petals linear.
Chionanthus. (73).
19. Stamens more numerous than the petals; leaves pal-
mately veined, opposite; fruit 2-winged. Some
Aceraceae.
a. Acer. (41).
20. Ovules 1 or 2 in each cavity. 21.
20. Ovules several or many in each cavity; stipules be¬
tween the opposite and pinnately compound leaves,
caducous; shrubs or small trees. Staphyleaceaf..
a. Staphylea. (37).
21. Leaves palmately veined, or compound. 22.
21. Leaves pinnately veined, simple, not punctuate. 23.
22. Leaves pinnately compound, alternate; climbing-
herbaceous vines with fruit an inflated 3-lobed
capsule; or trees with a globose or lobed berry.
Sapindaceae.
a Sapindus. (38).
22. Leaves palmately veined or pinnately compound; trees
or shrubs with opposite leaves and no stipules.
Aceraceae.
Trees of the Northern United States
3!)
a. Acer. (41).
22. Leaves 3-foliate, pellucid-punctuate, without stipules
Some Rutaceae.
a. Ptelea. (18).
23. Calyx minute: trees or shrubs with simple mostly
alternate leaves. Iucaceae.
a. Ilex. (36).
23. Calyx not minute; trees, shrubs, or woody climbers
ours with opposite leaves and with minute fu-
gaceous stipules. Celastraceae.
a. Euonymus. (35).
24. Perfect stamens 4, styles 2; leaves alternate, palmatelv
veined and lobed, or if pinnately veined then 2-
ranked. Hamamelidaceae.
See 13 above.
24. Stamens 5, 10, or many; styles 2-5; leaves alternate
with stipules. Rosaceae. (Mai.atae).
a. Leaves pinnate. Sorbus. (21).
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. (25).
c. Ovules many in each cavity (carpel). Cydonia. (24).
c. Ovules 1-3 in each cavity of the ovulary. d.
d. Usually with typical thorns; ripe carpels bony.
Crataegus. (26).
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. (22).
e. Leaves irregularly dentate or serrate, or more or
less lobed; pome without grit cells. Malus. (23).
40
Field Manual
24. Stamens 4 or 5, style and stigma 1; leaves opposite or
alternate. Cornaceae.
a. Ovulary. 2-locular, flowers bisporangiate. b.
a. Ovulary 1-locular, flowers diecious or imperfectly
diecious. Nyssa. (81).
b. Flowers cymose, not involucrate. Cornus. (79).
b. Flowers capitate, with an involucre of 4-6 large
white bracts. Cynoxylon. (80).
24. Stamens 4 or 5 on a flat disc which covers the 3-5-
locular ovulary; shrubs or trees with opposite leaves
and minute fugaceous stipules. Celastraceae.
See 23 above.
24. Stamens 5, styles usually 2-5; leaves bipinnate.
Araliaceae.
a. Aralia. (78).
—25—
25. Leaves opposite. 26.
25. Leaves alternate. 27.
26. Stamens 5-8; leaves palmately veined and simple or
if pinnately compound then the base of the petiole
covering the axillary buds. Aceraceae.
a. Acer. (41).
26. Stamens 2-4; leaves pinnately veined when simple.
or pinnately compound then the axillary buds
exposed. Oleaceae.
a. Flowers fasciculate or racemose-fasciculate, not
from prominent scaly buds; leaves compound.
Fraxinus. (74).
a. Flowers fasciculate, from scaly buds; leaves sim¬
ple. Forestiera. (75).
27. At least the staminate flowers in catkins or catkin¬
like spikes or spherical beads. 31.
27. Flowers not in catkins or catkin-like spikes or heads. 28.
28. With prominent stipular spines; leaves punctuate with
glands. Rutaceae.
a. Zanthoxylum. (17).
t ^ 1, - +- cninpc 9 Q
Trees of the Northern United States
41
29. Styles or stigmas 3 or 4; perigynous stamens 4-5,
alternate with the sepals; ovulary 2-5-locular, ovules
solitary in each cavity'. Rhamnaceae.
a. Rhamnus. (34).
29. Styles or stigmas 2; leaves 2-ranked; ovulary 1-2-
ovuled; stipules fugaceous. Ui.maceae.
a. Flowers in clusters on twigs of the previous sea¬
son, pith not diaphragmed. b.
a. Flowers on elongated twigs of the season; pith
interruptedly diaphragmed. Celtis. (50).
b. Flowers expanding before the leaves; bark in
rough ridges. Ulmus. (48).
b. Flowers expanding with the leaves; bark of trunk
scaling off like in the Sycamore. Planera. (49).
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 ever¬
green. Persea. (15).
a. Flowers monosporangiate, racemose or umbellate;
leaves deciduous, some of them lobed. Sassa¬
fras. (16).
30. Calyx 5-parted; stamens 10 or fewer; bark not aro¬
matic. Fabaceae. (Cassiatae).
See 15 above.
30. Calyx 5-parted; stamens 5-15; flowers epigynous; pith
solid but diaphragmed. Cornaceae.
a. Nyssa. (81).
31. Twigs with complete stipular rings; base of petiole
covering the axillary bud; flowers monecious, in
dense heads. Platanaceae.
a. Platanus. (47).
31. Twigs without stipular rings. 32.
32. Axillary buds superposed; staminate flowers in flexible
catkins ; leaves pinnately compound.
Juglandaceae.
a. Pith solid. Hicoria. (61).
a. Pith diaphragmed, with cavities. Juglans, (62).
42
Field Manual
32. Axillary buds not superposed or if so then the stam-
inate flowers not in flexible catkins; leaves sim¬
ple. 33.
33. Carpellate flowers epigynous; pith solid, with dia¬
phragms. Cornaceae.
a. Nyssa. (81).
33. Carpellate flowers hypogynous 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. (46).
34. Staminate and carpellate flowers not in dense spherical
heads unless the sap is milky; leaves not star¬
shaped. 35.
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-
cleft, carpellate flowers capitate. Toxylon. (52).
a. Twigs without thorns, b.
b. Staminate and carpellate flowers in ament-like
spikes. Morus. (51).
b. Staminate flowers racemose or spikate, the car¬
pellate capitate. Papyrius. (53).
35. Sap not milky. 36.
36. TBoth staminate and carpellate flowers in aments, the
carpellate flowers not subtended by a bur or cup. 37.
36. Carpellate flowers not in aments, subtended by a cup
or involucre; staminate flowers in flexible or some¬
what capitate aments. Fagaceae.
a. Staminate flowers capitate, ovulary 3-angled.
Fagus. (54).
a. Staminate flowers in slender aments, b.
b. Carpellate flowers 2-5 in each involucre, which be¬
comes prickly. Castanea. (56).
b. Carpellate flower 1 in each involucre, which con¬
sists of numerous scales. Quercus. (56).
Trees of the Northern United States
43
37. Ovulary 1-1-ocular, many seeded; seeds with a tuft of
cottony hairs. Salicaceae.
a. Stamens numerous; bracts fimbriate or entire,
buds with several exposed scales; pith 5-
angled. Populus. (64).
a. Stamens 2-10; bracts entire; buds with 1 outer
scale. Salix. (65).
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. (63).
38. Carpellate flowers 2 or more in each bract of the
ament; twigs and leaves not glandular dotted:
buds not clustered at the tip of the twig. Betulaceae.
a. Pith 3-angled; buds stalked; leaves not 2-ranked:
stamens 4. Alnus. (60).
.a. Pith not 3-angled; buds sessile; leaves 2-ranked. b.
b. Staminate flowers 3-6 in the axil of each bract,
with a calyx; carpellate flowers without a calyx;
stamens 2. Betula. (59).
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. (57).
c. Fruiting bract bladder-like, closed; bark of older
trunks scaly and fine-furrowed. Ostrya. (58).
—39—
39. 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 (pentacyelic) or more. 41.
4ft. Stamens united with the corolla, as many as the petals
and opposite them or twice as many or more. 42
44
Field Manual
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. (68).
a. Leaves evergreen, coriaceous, b.
b. Corolla somewhat irregular, campanulate, without
little sacs. Rhododendron. (66).
b. Corolla regular, saucer-shaped, 10-saccate, the
anthers at first held in the little sacs.
Kalmia. (67).
41. Choripetalous plants in which the petals are some¬
times partly or completely united,
a. Ovulary 1-locular (1 carpel) with 1 parietal pla¬
centa. 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. Sapotaceae.
a. Bumelia. (69).
42. Stamens twice as many as the lobes of the greenish-
yellow corolla or more; styles 2-8; plants mostly
monecious or diecious; leaves alternate, simple,
and entire. Ebenaceae.
a. Diospyros. (70).
43. Flowers regular, stamens usually 2. Oleaceae.
a. Chionanthus. (73).
43. Flowers irregular, zygomorphic; seeds numerous,
stamens 4, didynamous; pith with cavities. Some
— Scrophulariaceae.
Trees of the Northern United States
45
a. Paulownia. (76)\
43. Flowers irregular, zygomorphic; seeds numerous.
fertile stamens usually 2 with 3 vestiges; pith
solid. Bignoniaceae.
a. Catalpa. (77).
44. 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. 46.
45. Corolla yellow; stamens in several series. Symplocaceae.
a. Symplocos. (71)
45. Corolla white ; stamens in one series. Styracaceae.
a. Halesia. (72).
46. Stipules present; flowers in dense heads in our species;
usually blackening in drying. Rubjaceae.
a. Cephalanthus. (82).
46. Usually without stipules; flowers in compound cymes
in our species; not blackening in drying.
Caprifoliaceace.
a. Viburnum. (83).
CLASSIFICATION AND DESCRIPTION OF THE
SPECIES.
SPiERMATOPHYTA. SEED-PLANTS.
Phylum, CYCADOPHYTA.
Class, Ginicgoeae.
Order, Ginkgoales.
Ginkgoaceac. Ginkgo Family.
1. Ginkgo Kaempf. Ginkgo.
Trees with dichotomously veined, fan-shaped leaves on
thick, wart-like, persistent, dwarf branches.
Stamens and carpels in clusters on the dwarf branches,
appearing with the leaves.
1. Ginkgo biloba. L. Maiden-hair-tree. A large, beau¬
tiful and hardy tree with diecious flowers. Seed large, drupe¬
like. Autumn leaves orange. Introduced from China and
Japan ; should be commonly cultivated for ornament.
Phylum, STROBILOPHYTA.
Class, Coniferae. Conifers.
Order, Pinales.
Taxodiacecic. Bald-cypress Family.
2. Taxodium Rich. Bald-cypress.
Trees with feather-like, annually deciduous dwarf
branches with the numerous, small, narrow leaves usually
spreading into two ranks, 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.
I. Taxodium distichum (L) Rich. Bald-cypress. A
large tree, the old bark flaky in thin strips. The roots de¬
velop 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.
(ACG
Trees of the Northern United States
47
Pinaccac. Pine Family.
3. Picea Link. 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
cylindric. 2.
1. Twigs pubescent, brown; carpellate cones ovoid or
oval. 3.
2. Leaves usually 1-1 in. long; carpellate cones 2^-6 in.
long. P. abics.
2. Leaves usually not much over J in. long ; very glau¬
cous ; carpellate cones S-2 in. long. P. canadensis.
3. Leaves not glaucous ; cones deciduous at the end of
the first season. P. rubens.
3. Leaves glaucous ; cones persistent for two or more
seasons. P. mariana.
1. Picea a'oies (L.) Karst. Norway Spruce. A large
tree, conical in shape when young, with numerous stout spread¬
ing and drooping branches. Abundant in cultivation. Source
of Burgundy pitch. Native of Europe.
2. Picea canadensis (Mill.) B. S. P. White Spruce.
A slender tree sometimes with a strong skunk-like odor.
Leaves light green, slender, i-i in. long, very acute. An
important timber tree with light, soft, weak, and straight¬
grained wood. Newf. to Alaska, south to Me., Mich., and
S. Dak.
3. Picea rubens Sarg. 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 Alleghanies 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 ;
Field Manual
4*
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 spread¬
ing more or 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 flat 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 than the ovuliferous scale.
1. Carpellate bract serrulate, shorter than the ovulifer¬
ous scale or but little longer; leaves" obtuse. A
balsamea.
1. Carpellate bract aristate, longer than the ovuliferous
scale; leaves mostly emarginate. A. fraseri.
1. 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.
2. Abies fraseri (Pursh) Poir. Fraser Fir. A slen¬
der tree growing on the high Alleghanies. Bark smooth, with
resin blisters. W. Va., N. Car., and Tenn.
Trees of the Northern United States
49
6. Larix (Tourn.) Adans. Larch.
Trees with thick wart-like dwarf branches bearing a
cluster of deciduous needle-shaped leaves.
Tall pyramidal, monecious trees with horizontal or
ascending branches; carpellate cones small, erect, with thin
woody scales.
1. Carpellate cones small, in. long, oval or almost
globular; ovuliferous scales glabrous; native, grow¬
ing in bogs and wet places. L. laricina.
1. Carpellate cones rather large, 1-1J in. long ; ovulifer¬
ous scales finely tomentose on the back, cultivated
in dry ground. L. larix.
1. Larix laricina (DuRoi) Koch. Tamarack. A
slender tree with close or at length scaly bark. Wood hard,
durable, 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 larix (L.) Karst. European Larch. A beauti-
■ ful 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 hearing
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.
Carpellate cones woody with numerous carpels. Our most
important lumber trees.
1. Dwarf branches with 5 foliage leaves; ovuliferous
scales little thickened at the tip. P. strobus.
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.
Field Manual
50
2. Dwarf branches mostly with 2 foliage leaves ; some
of them may be with 3. 5.
3. Leaves 6-10 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 1-1 In. long; leaves
not glaucous; carpellate cones oblong-conic. P.
taeda.
4. Old sheaths about 4 in. long; leaves glaucous; car¬
pellate cones ovoid. P. scrotina.
5. Twigs glaucous ; resin-ducts parenchymatous ; car¬
pellate cones 14-3 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 resin¬
ous; prickles of the ovuliferous scales short and
small. P. echinata.
6. Leaves stout, 14-21 in. long; buds very resinous;
prickles of the ovuliferous scales long and stout.
P. virginiana.
7. Leaves 1-4 in. long, grayish-green or light green;
ovuliferous 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
without 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; ovulif¬
erous scales pointless when mature. P. resinosa.
8. Foliage dull; resin ducts parenchymatous; carpellate
cones lateral, ovoid-conic; ovuliferous scale with
a small prickle, P. laricio.
9. Leaves 24-4 in. long, grayish-green ; twigs orange or
brown : resin ducts parenchymatous ; carpellate
cones ovoid; 3-5 in. long. P. pmigens.
9. Leaves 4-24 in. long. 10.
10. Leaves 14-24 in. long, grayish-green; twigs dull
greenish-yellow or greenish-brown ; resin ducts
peripheral : carpellate cones ovate-conic, 2-3 in
long. P. silvestris.
Trees of the Northern United States 51
10. Leaves J-H in. long; resin ducts parenchymatous :
carpellate cones oblong-conic, 1-2 in. long, usually
upwardly 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, Ill. and la.
2. Pinus taeda L. Loblolly Pine. A large tree of
very rapid growth vyith spreading branches and thick, rugged
hark, flaky in age. Wood rather hard; much used for lumber
in the south. Often growing in old fields. N. J. to Fla., Ark.,
and Tex.
3. 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.
4. Pinus rlgida 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, char¬
coal, and coarse lumber. A source of turpentine to a limited
extent. In dry, sandy or rocky soil. N. P>. to Ont., Tenn.,
Ohio, W. Va. and Ga.
5. 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.
(1 Finns lan'cio Poir. Austrian Pine. A tall, open,
pyramidal tree of rapid growth with the thick spreading
branches in regular whorls. Often cultivated. From Europe.
7. Pinus silves'tris L. Scotch Pine. A large and val¬
uable 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.
Field Manual
52
8. Pinus banksiana Lamb. Jack Pine. A slender
tree with spreading- branches, the bark becoming flaky. Wood
light and rather soft. In sandy soil. N. B. and N. W. Terr.,
south to Me., N. Y., Ill., and Minn.
9. Pinus echinata Mill. Yellow Pine. A large tree
with spreading branches ; leaves sometimes in 3’s, sometimes in
2’s Wood rather hard and very valuabe ; much used as lum¬
ber. ‘Also furnishes some turpentine. Produces shoots from
stumps. In sandy soil. N. Y. to Fla., Ill., Okl., and Tex.
10. Pinus pungens Lamb. Table-mountain Pine. A
tree with spreading branches, the old bark rough and in
flakes, leaves sometimes in 3’s. 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.
Juniperaceae. Juniper 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 oppo¬
site, 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. occidental is.
1. Branchlets in a vertical plane with both sides alike;
carpellate cones erect, the scales with a prominent
horn-like process below the apex; seeds wingless.
T. orientalis.
1. Thuja occidentals L. American Arborvitae.
Usually a small conical tree with fan-like branches. Self-
Trees of the Northern United States
53
prunes twigs. Wood light and durable; used for posts, rail¬
road ties, etc. Usually in wet* soil and along the banks of
streams. __ N. B. to Man., south to Ohio and N. J., along the
Alleghanies to N. C., and to Ill. and Minn.
2. Thuja orientalis L. Chinese Arborvitae. A small
pyramidal or bushy tree with spreading and ascending
branches. Native of Asia. Cultivated in many forms.
9. Libocedrus Endl. Incense-cedar.
Evergreen trees with naked buds and small, scale-like,
appressed, opposite, 4-ranked, usually elongated leaves on
somewhat flattened branches; scales of the carpellate cone
4-6, the two upper fertile, not peltate. >
Tall, resinous aromatic trees with scaly bark, monecious ;
staminate and carpellate cones on separate hranchlets ; 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 dur¬
able in contact with the soil. From the Pacific coast; often
cultivated 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 point.
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.
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 and N. H. to N. J„ Fla., and Miss.
2i Chamaecyparis lazvsoniana (Murr.) Pari. Lawson
Cypress. A large tree with an abruptly enlarged base and a
spire-like crown of small horizontal or pendulous branches.
Field Manual
54
Bark often 10 in. thick. Wood light, hard, and strong,
abounding in fragrant resin. ‘Front the Pacific coast. Many
varieties in cultivation.
Subfamily, Juniperatae.
11. Juniperus 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.
Carpel late cones small, globose; plants usually diecious.
sometimes monecious, pungent aromatic; bark usually thin
and shreddy.
1. Leaves all sublate, prickly pointed, verticillate, slender,
mostly straight; cones axillary. J. cofnmums.
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. X.
S. to Alaska, south to X. J„ Ohio, Mich., Xeb., and in the
Rocky Mts. to X. 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 Tex.
Phylum, ANTHOPHYTA.
Class, Dicotylae. Dicotyls.
Subclass, Thalamiflorae.
Order. 'Ranales.
MagnoUaceae. Magnolia Family.
12. Magnolia L. Magnolia.
Shrubs or trees wth alternate, simple, entire leaves, not
truncate, and with complete stipular rings.
Trees of the Northern United States
od
Bark bitter aromatic ; flowers bisporatigrate, large, soli¬
tary; buds covered with connate, sheathing stipules; pith
usually diaphragmed but solid ; fruit aggregate, cone-like.
1. Leaves auriculate, glabrous. Leaf buds glabrous. M.
fraseri.
1. Leaves rounded dr truncate at the base, thin. Leaf
buds silky pubescent. M. acuminata.
1. Leaves acute at the base. 2.
2. Leaves light green beneath, 1-2 ft. long. Leaf buds
glabrous. M. tripeta-Ia.
2. Leaves glaucous beneath, 3-6 in. long. Leaf buds
pubescent. M. virginiana.
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 h-\
ft. long; flowers greenish-yellow. Wood soft, light, and dur¬
able : used for cabinet-work, pump-logs, and water-troughs.
X. 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.
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 Tex.
4. Magnolia fraseri Walt. Fraser Magnolia. A tree
with spreading branches and glabrous leaf buds. Leaves
elongated-obovate or oblong, auriculate, 4-2 ft. long ; flowers
white. In mountain woods. Va. and Ky. to Fla. and Miss.
Various Magnolias are in cultivation, the more common
one is Magnolia soulangiana, Soulange’s Magnolia, 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.
56
Field Manual
Buds with connate stipules ; flowers large, perianth
trimerous ; anthers linear, extrorse; fruit aggregate, cone¬
like. dry.
1 Liriodendron tulipifera L. Tuliptfee. A very large,
magnificent, rapid-growing tree with glabrous leaf-buds.
Mowers 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
ft in circumference. Wood light, soft, and straight-grained,
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, drawers, and for carving and toys. One of the best
woods for paneling. Should be extensively cultivated. Vt.
and R. I. to Fla., Mich.,- Ark., and Miss.
Anonaceae. Custard-apple Family-.
14. Asimina Adans. Papaw.
Frees or shrubs with alternate, 2-ranked. simple, entire,
pinnately veined, deciduous leaves and diaphragmed, solid pith.
Buds naked, silky ; bark with fetid odor ; perianth trimer¬
ous ; stamens numerous ; 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,
greenish-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 hill¬
sides. Ont. and N, Y. to Mich., Neb., Tex., and Fla.
I.auraceac. Laurel Family.
15. Persea (Plum.) Gaertn. Bay.
Aromatic, evergreen trees or shrubs with alternate, sim¬
ple. 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 dark red bark, lanceolate or oblong-lanceolate leaves, and
Trees of the Northern United States
puberulent or nearly glabrous leaves. Wood hard, strong,
bright red in color, and rather brittle; used for cabinet-mak¬
ing, and interior finish. Along streams and the border of
swamps. Del. to Fla., Ark., and lex.
16. Sassafras Nees and Eberm. Sassafras.
Trees with entire or 3-lobed, alternate leaves with 2
prominent lateral veins, with spicy aromatic bark and unequal
internodes.
Flowers diecious ; perianth 6-parted ; fruit a blue drupe.
1. Sassafras sassafras (L.) Karst. Sassafras. A large
rough-barked tree, the sap of the bark and leaves mucilagin¬
ous. Autumn leaves red, yellow, and green. Wood reddish,
light and rather soft, of coarse texture, durable ; used in
cooperage, for small boats, and fencing. 1 he bark of the
roots yields a powerful, aromatic stimulant Fruit pungent,
poisonous. Excessive doses of sassafras tea produce narcotic
poisoning. In dry or sandy soil. Me. to Ont., Mich., Iowa,
Fla., and Tex.
Order, Geraniales.
Rutaceae. Rue Family.
17. Zanthoxylum L. Prickly-ash.
Trees or shrubs with alternate, pinnately 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-locular.
Field Manual
1 Ptelea trifoliata L. Hoptree. A shrub or small
tree with sunken superposed axillary buds covered by the
petiole base. Lark and flowers with a disagreeable odor.
Wood light brown, heavy, and hard. In woods. Conn, to
Fla., Ont., Minn., Kan., and Mexico.
Simantbacccie. Ailanthus Family.
IF 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 larg'e brown pith; flowers diecious ;
the 5 samaras linear or oblong, usually twisted.
1. Ailanthus glandulosa Desf. Tree-of-heaven. A
large tree of rapid growth with thick branches and smooth
bark. Leaves ill-scented ; leaflets with green glands 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.
T iliac eae. Linden Family.
20. Tilia (Tourn.) L. Linden.
Trees with 2-ranked, simple palmately veined, inequi¬
lateral, serrate or dentate leaves and solid pith.
Flowers bisporangiate, pentamerous, stamens numerous :
dry drupaceous fruit in cymose clusters, the peduncle sub¬
tended by a broad membranous bract.
L Leaves glabrous or nearly so on both sides, except on
the veins and in their axils. 2.
1. Leaves glabrous above, pubescent beneath. T.
pubescens.
1. Leaves glabrous above, silvery-white beneath. T.
heterophylla.
2. Petals with scales at the base ; inflorescence without
bracts ; leaves comparatively large ; native. T.
americana.
59
Trees of the Northern United States
2. Petals without scales at the base; inflorescence with
large bracts ; leaves comparatively small ; cultivated.
T. europaea.
1. Tilia americana L. American Linden. A large,
straight-trunked tree with spreading 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, panelling 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 Gar,
Manitoba, Kan., and Tex.
2. Tilia pubescens Ait. Downy Linden. A small tree
growing in moist soil, mostly along the coast. Wood as in
T. americana but lighter in weight. Va. to Fla., west to Tex.
3. Tilia heterophylla Vent. White Linden. A tree
with larger leaves than either of the preceding species. Wood
weak, light brown. N. Y. to Fla., Ala., Ill., and Tenn.
4. Tilia europaea L. European Linden. A large tree
much cultivated in parks. Its name, Lin, was the origin of
the family name of Linnaeus.
Subclass, Calyciflorae.
Order, Rosales.'
Rosaceac. Rose Family.
Malatae. Apple Subfamily.
21. Sorbus (Tourn.) L. Mountain-ash.
Trees or shrubs with alternate, odd-pinnate leaves, ter¬
minal buds, cylindrical pith, and 3-5 bundlescars in the nar¬
row 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-accuminate ; fruit less than i in. in
diameter. 5. americana.
2. Leaflets obtuse or short-pointed; fruit more than ’
in. in diameter. 5“. scopuiina.
60
Field Manual
1. Sorbus americana Marsh. American Mountain-
ash. A small tree with smooth bark. Bark and unripe fruit
' er> astringent. Wood soft, light brown. In moist ground.
Much prized for ornamental planting. Newf. to Man., N.
Car., and Mich.
-■ 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.
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.
22. Pyrus (Tourn.) L. Pear.
Trees or shrubs with alternate, simple, pinnately-veined,
serrate leaves with long petioles ; with stipules or stipular
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.
23. Malus Mill. Apple, Crab-apple.
I rees 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. coronaria.
2. Leaves ovate, rounded or cordate at the base, often
somewhat lobed. M. glmcescens.
Trees of the Northern United States
61
2. Leaves ovate, acute or acuminate* at the apex and
acute at the base, on slender petioles; finely and
nearly evenly serrate. M. baccata.
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. malus.
1. Malus coronaria (L) Mill. Narrow-leaf Crab-apple.
A small tree usually with thorn-like stunted branches or
spurs. Leaves oblong, oblong-lanceolate, or oval, thick, shin¬
ing above, sometimes pubescent beneath when young, dentate
or often entire. Wood hard, reddish-brown. On low ground.
N. J. to Ill., Kan., Fla., and La.
2. Malus baccata (L.) Borck. Siberian Crab-apple. A
small spreading tree with compact crown. Pedicels very
slender; fruit small, not becoming mellow. Cultivated.
3. Malus glaucescens Rehd. Fragrant Crab-apple. -A
small tree with hard and sour fruit suitable for preserving.
Leaves ovate, to triangular-ovate, sparingly pubescent be¬
neath when young, sharply serrate and often somewhat lobed.
Wood soft and reddish-brown. On low ground. Ont. to
Mich., S. Car., Iowa, and Mo.
4. Malus ioensis (Wood) Britt. Iowa Crab-apple.
A small tree much resembling M. glaucesscens. Leaves ovate,
oval, or oblong, dentate, crenate or with a few rounded lobes,
white, pubescent beneath, at length glabrous above. Minn.,
Wis., and Ill. to Neb., Ky., La., and Okla.
5. Malus 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.
24. 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.
Field Manual
62
Flowers bisporangiate, perianth pentamerous, pome fleshy.
1. Cydonia cyddnia (L.) Karst. Quince. A low tree
with crooked stem and rambling branches. Cultivated for the
large sour fleshy fruit.
25. Amelanchier Medic. Juneberry.
Shrubs or small trees with alternate, simple, serrate, pin-
nately-veined leaves ; with 3 bundle scars, terminal bud, a
narrow 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.
L Leaves rounded, obtuse or subacute at the apex; top
of the ovulary woolly ; petals i-f in. long. A.
sanguinea.
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 canadensis (L.) Med. Common June¬
berry. A medium-sized tree with a small, red or purple,
sweet and edible, berry-like pome. Wood very hard, brown.
In dry soil. Nova Scotia to Ont., Fla., La., and Ark.
2. Amelanchier intermedia Spach. Swamp June¬
berry. A shrub or small tree growing in swamps and moist
soil. Variable. 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.
26. 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, perianth pentamerous, stamens
5-25 ; pome drupe-like with bony ripe carpels.
The species of Crataegus are at present in a very un¬
satisfactory condition. Probably many of those included
Trees ok the Northern United States OH
below are merely hybrids or forms of freely interbreeding
elementary varieties. Many of the specific English names are
also unsatisfactory.
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 j-1 in.
long; fruit black. (Douglasianae) . 54.
3. Petioles £ in. long or longer. 4.
3. Petioles less than J 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. (i.
5. Leaves broadest at the base. 12.
6. Leaves broadest toward the apex. 7.
6. Leaves broadest at the middle. 8.
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. Calvx-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. (Macracan-
thae). 21.
Field Manual
64
11. Leaves elliptic to ovate; calyx-lobes less deeply cut:
nutlets with shallow pits on the ventral faces.
(Brainerdianae) . 23.
12. Leaves i-2% in. long and wide, membranous; calyx-lobes
usually entire. 13.
12. Leaves 1-4 in. long and wide ; calyx-lobes usually serrate.
(Coccineae). 44.
13. Leaves yellow-green often slightly pubescent; fruit soft
at maturity. (Tenuifoliae) . 34.
13. Leaves blue-green, usually glabrous : fruit hard at
maturity. (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 1-24 in. long. C. berberifolia.
16. Styles and nutlets usually 2.
C. schizophylla.
16. Styles and nutlets usually 3-5. 17.
17. Lobes of the leaves irregular, obtuse; fruit globose.
C. denaria.
17. Lobes of the leaves regular, acute; calyx-lobes serrate.
C. fecunda.
— Punctatae. —
18. Fruit ellipsoidal ; nutlets usually 3 or 4. 19.
18. Fruit globose. 20.
19. Leaves bright yellow-green, slightly impressed-veined
above. C. cuneiformis.
19. Leaves dull gray-green, strongly impressed-veined above,
obovate, narrow. C. punctata.
20. Nutlets 2 or 3. C. margaretta.
20. Nutlets 4 or 5. C. suborbiculata.
— M acracanthac. —
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. calpodendron.
22. Fruit I in. thick or less ; leaves large. C. succulenta.
22. Fruit \ in. thick or less; leaves small. C. neofluvialis.
Trees of the Northern United States
( i»5
— ■ Braincrdianae. —
23. Fruit and corymbs pubescent; calyx-lobes sharply glan¬
dular-serrate; leaves serrate; styles and nutlets 2 or 3.
C. pertomentosa.
23. Fruit and corymbs glabrous; calyx-lobes remotely glan¬
dular-serrate. C. brainerdi.
— Rotundifoliae. —
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. lucormn.
26. Leaf-lobes acuminate. C. irrasa.
26. Leaf-lobes acute or obtuse. 27.
27. Calyx-tube prominent ; fruit subglobose. C. macauleyae.
27. Calyx-tube obscure. 28.
28. Leaves acutely lobed toward the apex ; calyx-lobes
glandular-laciniate. C. bicknellii.
28. Leaves not acutely lobed ; calyx-lobes glandular-mar-
gined only ; fruit globose, red, round in cross-section
C. chrysocarpn.
— Virides. —
29. Leaves ovate; lobes shallow; fruit yellow-red. C. ovata.
29. Leaves oblong-ovate lobes deep; fruit bright red, glaucous.
C. viridis.
— Intricatac. —
39. Foliage and fruit pubescent; corymbs villous. 31.
•30. Foliage, fruit, and corymbs glabrous. 32.
31. Fruit globose, greenish to reddish-brown. C. intricate i.
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.
straminea.
33. Leaves ovate to oval ; fruit globose or subglobose, red¬
dish-green to reddish-brown. C. boyntoni.
— Tcnuifoliac. —
34. Fruit ellipsoid, ovoid, or pyriform; calyx-lobes entire. 35.
34. Fruit compressed-globose or subglobose. 36.
35. Leaves much lobed ; fruit small, i-J in. thick, with rather
firm flesh. C. roanensis.
Field Manual
lif:
35. Leaves not conspicuously lobed ; fruit large, i-i in. thick,
with soft flesh. C. macrosperma.
36. Lobes of the leaves reflexed. C. grayana.
36. Leaf-lobes spreading or ascending. 37.
37. Terminal leaves cuneate. C. alnorum.
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. rugosa.
40. Fruit not conspicuously angled, only slightly pruinose.
C. filipes.
41: Lobes of the leaves deep, acuminate. C. Iciophylla.
41. Lobes of the leaves shallow, acute. 42.
42. Fruit without conspicuous angles. C. beata.
42. Fruit conspicuously angled. 43.
43. Leaves deltoid. C. gattingeri.
45. Leaves ovate. C. pruinosci.
— 'Coccineae. —
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. 40.
45. Leaves broadly ovate. 47.
46. Corymbs nearly glabrous. C. villipes.
46. Corymbs very pubescent. C. anoinala.
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. tC. albicans.
49. Leaves concave, 14-3 in. long, 14-21 in. wide. C. pringlei.
49. Leaves plane, 14-4 in. long, l^-3£ in. wide. C. coccinea.
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.
arnoldiana.
Trees of the Northern United States
67
51. Lobes narrow, deep, and acute; fruit ellipsoid-pyriform.
C. submollis.
— Oxyacanthae. —
52. Leaves ovate, 3-15-lobed or cleft. C. nionogyna.
Parvifoliae. —
53. Leaves small, subcoriaceous, corymbs 1-3-flowered.
C. uniflora.
— Douglasianae. —
54. Leaves subcoriaceous, petioles 1-r in. long. C. douglajii.
— • Cordatac. —
55. Leaves often conspicuously 3-5-lobed, petioles i-2 in.
long. C. phaenopyntm.
1. Crataegus crus-galli L. Cockspur Hawthorn. A
small tree with spreading branches and numerous slender
thorns. Leaves coriaceous, shining above, sharply serrate,
bruit ellipsoid-ovoid to subglobose, greenish to red, flesh
hard, remaining on the branches until late in the winter.
The best hawthorn for hedges. N. Y. to Ont., 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 tomentose beneath. Fruit subglobose to short-ellipsoid,
yellow, orange, 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 to¬
wards 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.
Field Manual
(58
Leaves oblong-obovate to oval, bruit short-ellipsoid to sub-
globose, orange-red, slightly pubescent. Rich bottom lands.
Ill. and Mo.
6. Crataegus cuneiformis (Marsh.) £ggl. Marshalls
Hawthorn. A small tree with widely spreading branches,
dark brown scaly bark, and numerous, often branched thorns.
Leaves oblanceolate-obovate. Fruit ellipsoid-pyriform, scar¬
let or dark red. N. Y. and Pa. to Va. and Ill.
7. Crataegus punctata Jacq. Dotted Hawthorn. A
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 Haw¬
thorn. A shrub or small tree with ascending branches form¬
ing a round crown. Leaves oblong-obovate to ovate, serrate
or doubly serrate, 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 compressed-globose, dull green to scarlet. In
lime-stone 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 subglobose, dark red.
N. S. to Minn., N. C., Neb., and Col.
11. Crataegus neofluvialis 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
Trees of the Northern United States
69
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.
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. New Eng. to Iowa
and Pa.
15. Crataegus laurentiana Sarg. Fernald’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. Ill. 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. Bicknell's 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
numerous thorns. Leaves ovate-orbicular or obovate, doubly
serrate or lobed, shining above. Fruit depressed-globose to
short-ovoid, red. N. S. and N. R. to Saskatch., south to N. C..
Neb., and N. M.
Field Manual
70
\
21. Crataegus ovata Sarg. Ovate-leaf Hawthorn. A
tree with yellow scaly bark. Leaves ovate-elliptic or obovate,
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.
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 toward the apex, dark green and shining above. Fruit
globose or compressed-globose, bright red or orange, glaucous.
Alluvial soil. Va. to Fla., Ind„ Ill., Kan., and Tex.
23. Crataegus intricata Lange. Biltmore 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 Haw'thorn. 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
oblong-ovate, serrate or doubly serrate with acute lobes. Fruit
globose, light red, without angles. Va. to S. C.
26. Crataegus straminea Beadle. Alleghany Haw¬
thorn. An irregularly branched shrub or small tree with oc¬
casional thorns. Leaves elliptic-ovate, doubly serrate or lobed.
Fruit pyriform to ellipsoid, angular, yellow-green. Rocky
hills. Vt. to Mich., south to Del., Ala., and Mo.
27. Crataegus boyntoni Beadle. Boynton's Haw¬
thorn. A round-topped, irregularly branched shrub or small
tree with occasional thorns. Leaves oval to ovate, doubly
serrate or slightly lobed. Fruit subglobose, orange-red or
red-brown. Shaly soil. Mass, to Mich., south to S. C. and
Tenn.
Trees of the Northern United States
28. Crataegus roanensis Ashe. Roan Mountain Haw¬
thorn. A shrub or small tree with ascending branches and
numerous curved thorns. Leaves ovate or oblong-ovate,
serrate with acute straight lobes. Fruit ellipsoid, ovoid, or
pyriform, crimson. Quebec to Was., N. C, and Tenn.
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 Maine 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 4-6 pairs of acuminate lobes. Fruit
subglobose to short ellipsoid, angular, dark cherry-red. N.
Eng. to Ont. and N. Y.
31. Crataegus alnorum Sarg. Edson’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 a flattened round crown. Leaves
broadly ovate to elliptic-ovate, slightly villous, serrate or
doubly serrate, sometimes lobed. Fruit glabrous to short-
ellipsoid, 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
elliptic-ovate, serrate or doubly serrate with 4 or 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 broadly
ovate, serrate or doubly serrate with 4-6 pairs of broad
acuminate 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,
glabrous. Fruit globose or compressed-globose, cherry-red.
Western N. Eng. to Mich, south to Pa.
72
Field Manual
36. Crataegus leiophylla Sarg. Maine's Hawthorn.
A large shrub or small tree with erect branches and numerous
thorns. Leaves broadly ovate, doubly serrate, with 3-5 pairs
of acuminate spreading lobes, 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
ellipsoid, slightly angular, crimson. Ont. to Pa.
38. Crataegus gattingeri Ashe Gattinger s Haw¬
thorn. A shrub or small tree with ascending branches form¬
ing an irregular 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 \Y. Va. and Tenn.
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,
pruinose, scarlet or purple. Rocky open woods. N. Eng. to
Mich., N. C. and Mo.
40. Crataegus vfllipes Ashe. Thinleaf Hawthorn. A
tree with strongly ascending branches. Leaves elliptic-ovate,
serrate or doubly serrate with 4-6 pairs of acute or acuminate
lobes, pubescent or scabrous. Fruit pyriform or ellipsoid,
crimson. Maine to Quebec to Mich., south in the mountains
to N. €.
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 pyri¬
form-ellipsoid, crimson. Quebec to Mass, and N. Y.
42. Crataegus coccinioides Ashe. Eggert's Hawthorn.
A shrub or small tree with spreading branches. Leaves
broadly ovate, doubly serrate, dark green above. Fruit sub-
globose, obtusely angled. Quebec to R. I., .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
Trees of the Northern United States
73
pyriform, pubescent, red. Western N. Eng. to Ill., south to
Pa.
44. Crataegus coccfnea 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
ellipsoid, red, somewhat edible. Of considerable decorative
value. Conn, to Ont., Ill., Del. and Pa.
45. Crataegus albicans Ashe. Tatnall’s Hawthorn.
A shrub or small" tree with spreading branches. Leaves
broadly ovate to oblong-ovate, doubly serrate or lobed. Fruit
subglobose 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,
serrate or doubly serrate with broad shallow lobes, tomentose
or scabrous above. Fruit globose or subglobose, bright crim¬
son, 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 scab-
rate. Fruit short-ellipsoid to pyriform, orange-red, slightly
tomentose, edible. Quebec to Mass, and N. Y.
48. Cr^Jaegus mollis (T. & G.) Scheele. Downy
Hawthorn. 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
glabrous above when mature. Fruit globose or subglobose,
red. Native of Europe. Sparingly escaped in the eastern
states.
50. Crataegus, uniflora Muench. Dwarf Hawthorn.
An irregular shrub or small tree with numerous, slender,
Field Manual
straight thorns. Leaves obovate to spatulate, crenate or
crenate-serrate, shining above. Corymbs 1-3 flowered. Fruit
ellipsoid, pyriform 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’ Hawthorn.
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 witff 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., Ill., and Ark. Naturalized northward to N. J„ Pa., and
Ohio.
Amygdalatae. Peach Subfamily.
27. Prunus (Tourn.) L. 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 present or self-pruned ; perianth pen-
tamerous; 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 vernation ;
stone of the drupe compressed ; inflorescence umbel¬
late or with only 1 or 2 flowers. 7.
2. Petioles usually not over i in. long; leaves ovate.
abruptly acute at the apex ; flowers corymbose, termin¬
ating twigs of the season. P. mahaleb.
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. 8.
3. Flowers in umbellate or corymbose clusters. 4.
3. Flowers in racemes. 6.
Trees of the Northern United States
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.
6. Leaves ovate-lanceolate to lanceolate; inflorescence more
or less corymbose ; drupe with thin sour flesh. P.
pennsylvanica.
5. Leaves ovate to ovate-lanceolate; inflorescence umbellate,
drupe with thick sour flesh. P. cerasus.
C. 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.
fl. 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 | as
long as the blade. 8.
7. Leaves abruptly long-acute or acuminate, ovate to round-
ovate ; petiole £ as long as the blade; flowers solitary
or in twos ; fruit velvety. P. armeniaca.
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. I).
8. Leaves mostly narrow and peach-like, firm and more or
less shining, glabrous; calyx lobes pubescent on both
sides. P. hortulana.
i). Calyx-lobes entire, pubescent within; fruit globose;
flowers white. P. americana.
If 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. allc-
ghaniensis.
Field Manual
7(5
Cherries.
1. Prunus virginiana L. Black Cherry. A large tree
with rough, black, flaky bark ; drupe globose, dark-purple
oi black, sweet but slightly astringent. Leaves oval, oval-
lanceolate, 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.
2. Prunus nana 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., Tex.,
Colo., and Ohio.
3. Prunus rnahaleb 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,
glabrous, fragrant. Drupes with thin flesh and slightly flat¬
tened stone. From Europe. Conn, to Ont., N. Y. to Ohio
ind Kan.
4. Prunus Pennsylvania 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,
serrulate. 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-acu¬
minate, 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,
Trees ok the Northern United States
77
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 arniemaca 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
serrate, rounded at the base, slender-petioled. Drupe with
a tough skin, globose, red or yellowish, edible. Often used
as a stock 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-acuminate, 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. Ill. to
Kan., Tenn., and Tex.
11. Prunus angustifolia Marsh. Chickasaw Plum. A
small tree with thorn-like stunted branches. Leaves acute,
serrulate, often rounded at the base. Drupe globose, red, and
edible. In dry soil. N. J. to Fla., west to Rocky Mts.
12. 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
acuminate, finely serrate, rounded at the base. Drupe pleas¬
antly acid, globose-ovoid, with a conspicuous bloom. Penn.
28. Amygdalus I.. Peach.
Trees or shrubs with alternate, simple, serrate, pinnately-
veined leaves with 2-4 disk-like glands at the edge of the
78
Field Manual
base of the blade, with terminal bud, stipular scars or stipules,
reddish 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.
Fabaceae. Pea Family.
Cjassiatac. Senna Subfamily.
29. 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. Out. and N. Y. to
Iowa, Neb., N. J., Fla., Tex.
30. Gleditsia L. Honey-locust.
Trees with alternate, evenly pinnate or bipinnate leaves,
superposed buds beneath the petiole base, and usually with
branched axillary thorns.
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. triacaivthos.
1. Pod obliquely oval, 1-seeded, not pulpy; leaflets thicker,
darker green, usually larger, ovate-lanceolate or
lanceolate, the margin more crenulate. G. aquatica.
1. Gleditsia triacanthos L. Honey-locust. A large
tree of rapid growth, usually w'ith stout branching or simple
thorns and with rough bark, the catkin-like racemes often
Trees of the Northern United States
79
appearing 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 Tex.
2. Gleditsia aquatica 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.
31. Gymnocladus Lam. Coffee-bean.
Trees with alternate, evenly bipinnate leaves, sunken
superposed axillary buds, and large chocolate-colored pith.
Flowers greenish, diecious, both types with vestages of
the opposite sporophylls; 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, or 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 Okla.
Fabatae. Pea Subfamily.
32. Cladrastis 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.
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.
80
Field Manual
• 33. Robinia 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 sprout¬
ing 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 poison¬
ous. Wood brown, the sap-wood yellow. Va. to Ga. Also
escaped in Middle and Eastern States.
Order, Celastrales.
Rhamnaccac. Buckthorn Family.
34. 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 raono-
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
diecious or imperfectly monosporangiate. R. cathartica.
Trees of the Northern United States
81
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 Tex.
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.
Eastern states.
Celastraceae. Stafftree Family.
35. Euonymus (Touru.) 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-locular dehiscent
capsule ; seeds enclosed in a red aril.
1. Flowers purple; cymes 0-15 flowered; winter buds long-
pointed with long bud scales. E. atropurpureus.
1. Flowers greenish yellow; cymes 3-7 flowered; winter
buds very short pointed with short bud scales. E.
curopacm.
1. Euonymus atropurpureus Jacq. Wahoo. A high
shrub or small tree with green, obtusely 4-angled twigs.
Leaves dark red and fruit very ornamental in autumn. Self¬
prunes small twigs by basal joints. Wood nearly white. Ont.
to Fla., Mont, and Okla.
2. Euonymus europaeus L. Spindletree. A shrub or
small tree resembling the preceding. Self-prunes twigs. Cul¬
tivated from Europe. Escaped. N. Y., N. J. and Va.
Ilicaceae. Holly Family.
36. '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 ; anad with berry-like drupes con¬
taining several small stones.
Flowers small, in axillary clusters or solitary, mostly
•imperfectly diecious.
82
Field Manual
1. Leaves thick, persistent, evergreen, spiny. I. opaca.
1. Leaves thin, deciduous, not spiny. 2.
2. Leaves small, obovate or spatulate, crenate; nutlets of
the fruit ribbed. I. decidua.
2. Leaves large, ovate or lanceolate, sharply serrate, nutlets
ribbed. /. montana.
1. Hex 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 Tex.
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. In 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 Tex.
Staphyleaceae. Bladdernut Family.
37. Staphylea L. Bladdernut.
Shrubs or small trees with opposite trifoliate serrate
leaves.
Stipules caducous; flowers in axillary racemes or panicles,
white, bisporangiate, regular; capsule large and bladdery,
triocular.
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.
Trees of the Northern United States
83
Order, Sapindales.
Sapindaceae. Soapberry Family.
38. Sapindus (Tourn.) 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.
- 39. Koelreuteria Laxm.
Trees with alternate, odd-pinnate or bipinnate 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 spon¬
taneous from seed in Indiana.
Aesculaceae. Buckeye Family.
40. Aesculus L. Buckeye, Horse-chestnut.
Trees or shrubs with opposite palmately compound leaves.
Flowers imperfectly monosporangiate, zygomorphic, in
terminal panicles ; capsules leathery, containing large shining
nut-like seeds.
1. Flowers white, mottled with yellow and purple;
leaflets abruptly acuminate; winter buds gummy;
capsule 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.
84
Field Manual
2. Capsule spiny, stamens exserted. 3.
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-like small tree. A. arguta.
1. Aesculus hippocastanum L. Horse-chestnut. A
large tree with very resinous, gummy winter buds. Autumn
leaves orange. The seeds are poisonous 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., Midi., Neb., and Okla.
3. Aesculus arguta Buckl. Western Buckeye. A
shrub-like small tree with smooth bark. On flood plains.
Mo. and Kan. to Texas. Reported 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,
woodenware, and paper pulp. Aesculus octandra hybrida
(DC.) Sarg. has purplish or pink flowers, leaflets pubescent
beneath, and light brown bark. Penn, to Ga„ Iowa and Tex.
Aceraceae. Maple Family.
41. Acer (Tourn.) L. Maple.
Trees or shrubs with opposite leaves, with 3-5 bundle
scars in the narrow, contiguous leaf 'scars, and with a ter¬
minal bud showing several pairs of visible scales.
Sap watery or sometimes milkys often saccharine; fruit a
2-winged samara. Usually diecious or imperfectly diecious.
1. Leaves pinnate or trifoliate; twigs green, glaucous.
A. negundo.
1. Leaves simple. 2.
Trees ok the Northern United States
8-5
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 are 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. platanoides.
4. Leaves with watery or frothy sap, pale and nearly glab¬
rous 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. saccharum.
5. Leaves very sharply and finely serrate, 3-lobed at the
outer end, widest above the middle, the lobes
abruptly narrow-acuminate, brown pubescent below
when young ; twigs green, striped with darker lines ;
flowers racemed, terminal, unfolding after the leaves.
A. pcnnsytvanicum.
5. Leaves dentate-serrate or lobed, not abruptly narrow-
acuminate ; twigs not striped, (i.
(i. Leaves broadly 3-o-lobed, the lobes rather regularly
and continuously dentate-serrate or dentate-crenate ;
flowers recemed, terminal, unfolding after the
leaves. 7.
6. Leaves usually with 3-7 slender, long and pointed
lobes, the lobes irregularly or interruptedly serrate
or serrate-dentate; flowers in dense sessile lateral
clusters, appearing before the leaves. 8.
80
Field Manual
7. Leaves longer than wide, slightly 3-lobed at the outer
end, usually only very slightly lobed at the lower
end, not glaucous below; bark of twigs green or
grayish ; racemes erect : a shrub, rarely a small tree.
A. spicatum.
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 a-lobed, lobes slender, acute,
white and glaucous beneath; notches between the
lobes often somewhat rounded; fruiting pedicel
short and stiff. 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; petals
present. A. rubrum.
1. Acer platanoides 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 pseudo-platanus L. Sycamore Maple. A line tree
with spreading branches. Leaves deeply 3-5 lobecl. Self-
prunes. Much cultivated.
3. Acer pennsylvanicum L. Striped Maple. A small
tree with smoothish 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
beneath at least when young. In damp rocky woods. Newf.
to Man., south to N. Car., Tenn., Minn., and Towa.
Trees of the Northern United States
87
5. Acer saccharum Marsh. Sugar Maple. A large
tree with yellow or sometimes red leaves in autumn. Leaves
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 tough-; used for fuel, interior
finish, furniture, keels of boats and ships, implements and
machinery, sucker rods, rims of bicycle wheels, piano action,
school apparatus, large wood type, tool and broom handles,
and wood carving. Newf. to Man., south to Fla. and Tex.
(i. Acer nigrum Mx. 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. Leaves sharply 3-5-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 autumn. Self-pruning like the preceding. In
swamps and low ground, also on moist hillsides. N. S. to"
Man., 'Fla., Neb., and Tex.
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,
acuminate, coarsely and irregularly dentate, truncate or
slightly cordate 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
Field Manual.
88
and of slight value. Along streams. Planted on the prairies
for small groves and wind breaks. Maine to Man., Fla., Kan.
and Mex.
Anacardiaceae. Sumac Family.
42. 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 ;
stamens five, styles three; drupe red.
1. Petioles not completely covering the axillary buds;
leaflets entire: rachis of the leaf wing-rnargined ;
leaflets 7-31 ; twigs and the red drupes pubescent.
R. copallina.
1. Petioles covering the axillary buds; leaflets serrate. 2.
2. Leaves and twigs velvety-pubescent. R. hirta.
2. Leaves and twigs glabrous, somewhat glaucous. R.
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 brown. In dry
soil. Me. and Ont. to Fla., Minn., Neb. and Tex.
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. Xoted 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
Trees of the Northern United States
Si)
43. Toxicodendron. Poison-Sumac.
Small trees or shrubs, ours with alternate pinnate leaves
with entire leaflets, with poisonous resinous sap, and with
glabrous or slightly pubescent drupes.
Flowers small, in axillary panicles, imperfectly bispor-
angiate ; 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., Out., Minn., Mo. and La.
44. Cotinus Adans. Smoketree.
Small trees or shrubs with alternate, simple pinnately
\eined, 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. Pilade of the leaf slightly decurrent on the petiole,
thin, glabrous or slightly pubescent beneath. C.
americaniis.
1. Leaves mostly rounded or obtuse at the base, cori¬
aceous, more pubescent. C. cotinus.
1. Cotinus americanus Nutt. American Smoketree.
A small wide-branched tree. Wood soft, orange-yellow,
yielding a rich dye. Mo. and Okla. to Tenn. and Ala.
2. Cotinus cotinus ( L. ) Sarg. European Smoketree. A
small tree, native of Europe, frequently cultivated.
Subclass, Amentiferae.
Order, Platanales.
Hanmmelidaceac. Witch-hazel Family.
Subfamily, H amaniclidcitac .
45. Hamamelis L. Witch-hazel.
Shrubs or small trees with 2-rank'ed, 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.
!)0
Fikli) Manual
1. Hamamelis virginiana L. Witch-hazel. A shrub
or small tree with 2-ranked leaves and stalked buds. Blooms
in late autumn. Wood hard. In low ground and on hanks.
N. B. and N. S. to Minn., Mo., Fla. and Tex.,
Subfamily, Altingiatae.
46. Liquidambar L. Sweet-gum.
Trees with alternate, simple, palmately veined, fragrant,
star-shaped, serrate leaves and 5-angled pith.
Sap resinous, aromatic ; flowers monecious, in heads, the
staminate clusters racemose; capsules in a dense spiny glob¬
ular head.
1. Liquidambar styraciflua L. Sweet-gum. A fine
large tree with wide spreading branches, the twigs often cov¬
ered with corky ridges. Leaves with a peculiar sweet fra¬
grance 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. Some¬
times used as a substitute for black walnut. Used for fur¬
niture, veneer, wooden plates, plaques, baskets, hat blocks
and wagon hubs. In low ground. Conn., N. Y. and Ohio to
Fla., Ill.. Mo., and Mex.
Platanaceae. Planetree Family.
47. 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,
monecious, without perianth; fruit in pendant spherical heads
composed of numerous small nutlets.
1. Bark exfoliating in small plates; leaves 5-angled only
slightly 3-lobed, or seldom slightly 5-lobed. P
occidentalis.
1. Bark exfoliating in large plates; leaves somewhat 5-
lobed, in some varieties deeply lobed. P. orientalis.
1. Platanus occidentals L. Sycamore. A very large
tree, the largest in the northeastern United States, with
whitish or green bark which peels off freely in thin plates:
Trees of the Northern United States
91
the largest trunks usually hollow, sometimes as much as 42
ft. 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, cab¬
inet-work, and finishing lumber. Along the banks of streams
and in moist ground but grows well in ordinary mesophytic
conditions. Me. to Ont. and Minn., Fla., Kan. and Tex.
2. Platanus orientalis L. Oriental Planetree. A large
tree much like the preceding, but usually with a comparatively
short, massive trunk and a broad round crown. Leaves more
cut and becoming smooth earlier. Occasionally planted.
From Western Asia and Eastern Europe.
Order, Urticat.es.
Ulmaceae. Elm Family.
'48. Clmus (Tourn.) L. Elm.
Trees with alternate, 2-ranked, pinnately straight-veined,
inequilateral, doubly serrate leaves and sessile axillary buds.
Flowers bisporangiate or imperfectly bisporangiate, in
clusters 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 mucilagious. 2.
1. Leaves smooth or sometimes somewhat rough
above. 3.
2. Inner bark very mucilaginous, buds rusty-downy,
samara much less than 1 in. long. U. fulva.
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. americana.
3. None of the branches with corky ridges; twigs glab¬
rous or nearly so, not self-pruned; samara glab¬
rous or nearly so, deeply notched. U. camp e sir is.
3. Some or all of the branches corky-winged, or twigs
. puberulent, self-pruned; samara- faces pubescent. 4.
92
Field Manual
4. Mcst of the branches with corky wing-like ridges ;
twig's glabrous or nearly so; leaves 1-3 in. long.
U. alata.
4. Branches often with corky wing-like Vidges ; twigs
puberulent : leaves 2-5 in. long. U. thomasi.
1. Ulmus americana L. White Elm. A large tree of
rapid growth, with the bark in thick, rough ridges ; much
cultivated in cities and along roadsides. 4 ranks up to 33 ft.
in circumference. Samara ovate-oval, its faces glabrous.
Wood heavy, hard, flexible, and very tough : used fcr 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 cn bluffs and on the
flood plains of rivers and creeks. Graceful in form and very
suitable for cultivation. Xewf. to Man., Ida. and Tex.
2. Ulmus thomasi Sarg. Cork Elm. A large tree
with puberulent young twigs, the branches or seme 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 alata 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 Tex.
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
glabrous. A good timber tree. Cultivated, front Europe.
5. Ulmus fulva Mx. Slippery Elm. A medium-sized
tree with rough grayish-brown fragrant bark and rough-pu¬
bescent twigs. Samara oval-orbicular, pubescent over the
seed. Inner bark mucilaginous and medicinal. Wcod hard
and strong but splitting easily when dry.. Along streams, on
flood plains and on hills. Quebec to X. Dak., 1-la. and lex.
f>. Ulmus montanci With. Scotch Elm. A large tree
with spreading branches, or in some varieties with strictl\
Trees ok the Northern United States
93
upright branches; branchlets pubescent. Leaves rough above,
pubescent beneath, doubly serrate, often somewhat 3-lobed at
the apex. Many varieties fine for planting. From Europe.
49. Planera Gmel. Planertree.
Trees with alternate, two-ranked, straight-veined, in¬
equilateral, 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 Tex.
50. Celtis (Tourn.) L. blackberry.
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 glabrous, especially the fruiting ones, or
pubescent. C. occMcntalis.
1. Leaves entire or few-toothed, small. C. mississip-
picnsis.
1. Celtis occidentals L. Common Hackberry. A
medium-sized tree with rough bark. Commonly much dis¬
torted 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. Quebec to Man., N. Car., Mo., Kan. and Okla.
2. Celtis mississippiensis Bose. Southern blackberry
A medium-sized tree with light gray, rough bark. Usually
in dry soil. Va. to Ill., Mo., Kan., Fla., and Tex,
94
Field Manual
Moraceae. Mulberry Family.
Subfamily, Moraiae.
51. 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, pubescent 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 con¬
tact with the ground, very valuable for posts ; used for farm
implements, in cooperage, “acid wood,” and ship building. In
rich soil Vt. and Ont. to Mich., S. Dak., Fla. and Tex.
2. Morus alba 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 feeding silk-worms. Wood suitable for posts. Al¬
though growing best in rich moist soil, it does well in quite
dry regions and should be much planted on the dry prairies,
especially varieties with the better grade of berries. Intro¬
duced from the old world. Me. and Ont., to Fla. and Kan.
52. Toxylon Raf. Osage-orange.
Small trees with alternate simple entire leaves, typical
axillary thorns, and milky sap.
Flowers diecious, the staminate racemose, the carpellate
capitate ; fruit a large spherical, greenish or yellowing aggre¬
gate.
1. Toxylon pomiferum Raf. Osage-orange. A small
thorny tree much planted for hedges. Leaves ovate to ovate-
lanceolate, acuminate or taper-pointed. Wood very heavy, ex¬
ceedingly 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
95
Treks ok the Northern United States
acquire a strong liking for the young shoots and eat them
in large quantities without apparent ill effects. Mo. and Kan.
to Tex. Escaped in Ohio and other eastern states.
53. Papyrius Lam. Paper-mulberry.
Trees with alternate simple 2-ranked leaves having two
prominent side-ribs from the base, with milky sap, and with
downy twigs.
Flowers diecious, the staminate in ament-like spikes, the
carpellate capitate; fruit a globular head of red drupes.
1. Papyrius papyrifera (L.) Ktz. Paper-mulberry.
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.
Order, Fagales,
Fagaceae. Beech Family.
54. Fagus (Tourn.) L. Beech.
Large trees with alternate 2-ranked simple equilateral
pinnately straight-veined dentate leaves, with a vein for each
tooth, and with prominent green medullary rays.
Winter buds usually very long-pointed; flowers monecious ;
nut 3-angled, enclosed in a_ 4-valved bur with soft, short
prickles.
1. Fagus grandifolia Ehrh. American Beech. A
large tree, the lower branches spreading. Autumn leaves pure
yellow. Nut sweet and edible. Wood hard, heavy, light-
colored, rather close-grained, not durable in the ground ; used
for making chairs, handles, plane-stocks, shoe-lasts, in turnery,
and for “acid wood.” In rich but not necessarily deep soil.
N. S. to Ont. and Minn., Mo., Fla., and Tex.
55. Castanea (Tourn.) Hill. Chestnut.
Trees or shrubs with simple alternate equilateral pinnately
straight-veined serrate leaves, with a vein for each tooth,
with 5-angled pith and inconspicuous medullary rays.
Flowers monecious; fruit a rounded coriaceous nut;
several in a globose, mostly 4-valved involucre covered with
long prickles.
Kiei.i) .Manual
lit;
1. Leas es green on both sides ; large trees. C. dentata.
1. Leaves densely white-tomentose beneath ; shrubs or small
trees. C. pumila.
Castanea dentata (Marsh.) Borkh. Chestnut. A
large tree of very rapid growth with rough bark in longi¬
tudinal ridges. Nut sweet and edible. Wood soft, light, and
coarse-grained, durable ; used for cabinet-work, railway ties,
posts, cooperage, “acid wood,” and telegraph poles. Sprouts
freely from stumps. In rich gravelly or sandy soil. Me. to
Mich., Ga., and Ark.
2. Castanea pumila (L.) Mill. Chinquapin. A shrub
or small tree. Nut very sweet. Wood much like in C. dentata
but heavier. In dry soil. N. J. to Ind., Mo., Fla., and Tex.
•56: 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 i-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 autumn
of the second year. 11.
2. Leaves crenate or dentate, not lobed. 3.
2. Leaves pinnatified or pinnately lobed. 7.
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. O.
muhlenbcrgii.
4. Shrub or low tree, leaves obovate or oval ; seed edible.
Q. prinmdes.
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. O. bicolor.
1 REES OF THE NORTHERN UNITED STATES
97
(>. Teeth of the leaves acute or mucronnlate; bark white,
flaky; seed sweet and edible; fruit. short peduncled
or sometimes nearly sessile. Q. michauxii.
C>. Teeth of the leaves rounded; bark close; seed edible;
petioles slender; peduncles equalling or shorter than
the petioles. Q. prinus.
7. Mature leaves pale, or glaucous and glabrous below. 8.
i. Mature leaves pubescent or tomentose below, lyrate-pin-
natifid. 9.
8. Bark separating in thin scales, light gray or light brown ;
cup shallow ; bracts thick and warty. O. alba.
8. Rark furrowed and ridged, not scaly, dark gray or dark
brown ; cup hemispherical, with imbricated, appressed
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 upper 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.
11. Leaves pinnatifid or pinnately lobed. 14.
]-■ Leaves oblong or lanceolate, tomentulose beneath. 0.
imbricaria.
12. Leaves linear-oblong, green and glabrous on both sides.
Q. phellos.
13. Leaves spatulate, glabrous on both sides; cup saucer¬
shaped, acorn globose-ovoid. Q. nigra.
lo. Leaves obovate-cuneate, brown-floccose beneath ; cup
deep, acorn ovoid. Q. marylandica.
14. Leaves white or gray-tomehtose below. 15.
14. Leaves green on both sides. 17.
15. Leaf-lobes lanceolate or linear-lanceolate, long; large
trees. 16.
Field Manual
its
15. Leaf-lobes triangular-ovate, short; shrubs or low trees.
Q. ilici folia.
16. Leaves rounded or obtuse at the base, 3-5 lobed; lobes
linear or lanceolate, often falcate. Q: triloba.
16. Leaves cuneate to truncate at the base, 5-11 lobed; lobes
triangular. Q. pagodaefolia.
17. Leaves usually pubescent below; winter buds tomentose-,
cup turbinate or hemispherical; inner bark orange.
Q. velutina.
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 shallow, saucer-shaped, much broader
than deep. 20.
19. Leaves dull, paler beneath; acorn ovoid, cup depressed-
hemispheric. Q. borealis.
19. Leaves shining on both sides, lobed to near the mid-rib;
acorn ovoid; cup top-shaped. Q. coccinea.
20. Leaves dull; cup 1-1 in. broad; acorn ovoid or elon¬
gated. Q. rubra.
20. Leaves shining deeply pinnatifid; cup 1-1 in. broad;
acorn subglobose or ovoid. Q. palustns.
Chestnut oaks.
1. Quercus prinus L. Rock Chestnut Oak. A large
tree with brown bark, ridged close or slightly flaky. Leaves ob¬
long, oblong-lanceolate, or obovate, coarsely crenate, glabrous
above, finely gray-tomentulose beneath, petioles slender; cup
hemispheric, 1-11 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 Ont., Ala., and Tenn.
2. Quercus 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, 1-11 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 Tex.
99
Trees of the Northern United States
3. Quercus muhlenbergii Engelm. Chestnut Oak. A
tree with close gray bark. Leaves oblong, lanceolate, or
obovate, coarsely toothed with acute teeth, shining above,
pale and gray-tomentulose beneath, 4-6 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 lime stone ridges. Vt. and
Ont. to Minn., Ala.. Neb., and Tex.
4. Quercus prinoides Will-d. Scrub Chestnut Oak. 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 Tex.
5. Quercus bicolor Willd. Swamp White Oak. A
large tree with flaky gray bark. Leaves obovate, or oblong-
obovate, coarsely toothed or sometimes lobed nearly to the
middle, dull and g'labrous above, densely white-tomentulose
beneath ; peduncles of the hemispheric 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 ft. in circumference and with light gray bark-
scaling off in thin plates. Leaves obovate, pinnatifid, lobes
oblong, toother 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 Laves
red and russet. Self-prunes extensively. Wood light-colored,
hard and tough ; valuable for many purposes ; an ideal wood
for railroad 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. stellata and O. Prinus. Me.
to Out., Minn., Fla., Kan., and Tex.
100
Field Manual
7. Quercus robur L. English Oak. A large strong
tree with stout more or less spreading branches forming a
broad round-topped head; self-prunes. Many forms are cul¬
tivated for ornament, including yellow-leaved and cut-leave
…[truncated]