field manual of trees

Survival, Water, Medical Field Manuals

Military Manuals

John H. Schaffner

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FIELD  MANUAL 
of  TREES 


Including  Southern  Canada  and  the 
Northern  United  States  to  the  South¬ 
ern  Boundary  of  Virginia,  Kentucky 
and  Missouri,  Westward  to  the  Limits 
of  the  Prairie 


THIRD  EDITION 


By 

JOHN  H.  SCHAFFNER 

Professor  of  Botany 

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


R.  G.  ADAMS  &l,  COMPANY 
Columbus,  Ohio 


Copyright  1926 

BY 

John  H.  Schaffner 


PREFACE 


This  little  manual  represents  a  revision  of  the  author’s 
former  “Trees  of  Ohio  and  Surrounding  Territory,”  and  at¬ 
tempts  to  carry  out  more  definitely  the  idea  of  having  a 
convenient  guide  by  which  it  is  possible  to  study  our  trees 
at  any  season  of  the  year.  The  keys  have  been  made  very 
complete  so  that  no  difficulty  should  be  encountered  in  iden¬ 
tification  except  in  the  case  of  closely  related  species.  No 
elaborate  technical  descriptions  have  been  given  but  a  few 
brief  notes  are  added  in  connection  with  each  species,  calling 
attention  to  economic,  ecological,  or  other  data  of  general 
interest.  Characters  given  in  the  keys  are  usually  not  re¬ 
peated  in  the  descriptions.  A  definite  characterization  is 
also  given  for  each  germs.  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  appropri¬ 
ate  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  inter¬ 
est  in  nature.  When  the  tree  has  once  been  identified  its 
peculiarities  should  be  learned  by  direct  observation  until  its 

(3) 


4 


Field  Manual 


individuality  becomes  perfectly  familiar.  In  winter  one  cq.n 
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. 


Only  minor  changes  and  corrections  have  been  made  in 
the  third  edition,  so  the  Manual  remains  practically  as  it 
was  originally  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  at¬ 
tempting  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  lai’gely 
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  th«.  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 


6 


Field  Manual 


tlie  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  he  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  impoitant 
function  of  the  leaves  is  the  transpiration  of  the  surplus 
water  brought  up  from  below.  The  water  transpired  by  a 
large  tree  in  a  single  day  is  often  very  great  in  amount.  The 
leaves  are  also  important  breathing  organs,  although  not  ex¬ 
clusively  so;  for  all  the  living  cells  in  the  entire  plant  carry 
on  the  process  of  respiration. 

The  system  of  branching  in  the  crown  may  be  of  various 
types.  If  the  main  trunk  of  a  tree  extends  upward  through 
the  crown  to  the  tip  it  is  said  to  be  excurrent,  as  in  the  larch 
and  Austrian  pine.  When  the  terminal  bud  has  no  pie- 
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.  Excurrent  trees  are  often  spire-shaped  like 
the  Norway  spruce;  while  deliquescent  stems  commonly  give 
rise  to  dome-shaped  crowns,  as  in  the  white  elm.  If  the 
terminal  bud  withers  or  is  self-pruned,  as  in  the  linden,  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 


'Trees  of  the  Northern  United  States 


7 


produced,  although  this  is  never  perfect  and  can  usually  be 
detected  by  careful  examination.  In  most  trees  the  inner  part 
of  the  wood  and  the  pith  are  dead  and  this  is  called  the  heart 
wood  or  duramen,  while  the  outer  wood  is  lighter  in  color 
with  living  cells  next  the  cambium  layer,  and  is  called  the 
sap-wood  or  alburnum.  Sometimes  there  is  a  striking  dif¬ 
ference  in  the  color  of  the  two  parts.  Strands  of  cells  pass 
from  the  pith  or  annual  rings  through  the  wood  to  the  bark. 
These  are  called  medullary  rays.  The  peculiar  qualities  of 
wood  are  due  to  the  character  of  its  cells  which  have  their 
walls  lignified  or  thickened  by  deposits  of  lignin  and  cellulose. 

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

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


8 


Field  Manual 


leaves  at  the  end  of  each  growing  season  by  the  formation 
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  dur¬ 
ing  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  dea9‘  branches  by  form¬ 
ing  a  collar  of  tissue  from  the  cambium  layer  around  the  base 
of  the  dead  branch,  which  finally  covers  over  the  wound 
when  the  dead  member  falls  off.  This  process  is  known  as 
natural  pruning.  By  the  formation  of  a  similar  callus  other 
wounds  are  covered  up.  There  is  still  a  more  remarkable 
process  present  in  many  trees  by  which  surplus  living 
branches  are  cut  off  in  one  way  or  another.  Terminal  and 
lateral  buds  are  also  commonly  cut  off.  This  process  of 
abscission  is  known  as  self-pruning.  The  most  common 
method  is  by  the  formation  of  a  cleavage  plane  in  a  basal 
joint  or  in  the  annual  nodes  of  growth.  In  some  genera 
brittle  zones  are  produced.  The  self-pruning  process  is  very 
highly  developed  in  the  cottonwood,  white  oak,  white  elm, 
and  silver  maple. 

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

All  of  our  native  trees  bear  flowers  and  seeds.  After  ar¬ 
riving  at  a  certain  age  depending  on  the  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  gynecium  composed  of  carpels.  The  two  essential  sets 
of  organs  in  the  flower  are  the  stamens  and  the  carpels. 
These  are  the  sporophylls  and  may  both  be  in  the  same 
flower,  when  the  flower  is  said  to  be  bisporangiate  or  in 


'Trees  of  the  Northern  United  States 


9 


separate  flowers,  when  the  flower  is  monosporangiate.  If 
the  staminate  and  carpellate  flowers  are  on  one  individual 
the  plant  is  monecious,  if  on  two  distinct  individuals  the 
plant  is  diecious.  In  this  ease  the  plants  are  spoken  of  as 
staminate  trees  and  carpellate  trees.  The  stamens  produce 
microsporangia  and  the  carpels  megasporangia  or  ovules.  In 
the  Anthophyta  the  carpel  usually  has  three  parts  called 
stigma,  style  and  ovulary,  the  ovules  being  completely  in¬ 
closed  in  the  ovulary.  Commonly  all  the  carpels  of  the 
gynecium  are  grown  together  and  in  such  cases  a  compound 
ovulary  is  produced  with  one  or  more  cavities. 

In  the  gymnosperms,  which  include  the  Strobilophyta  or 
our  common  evergreens,  the  flower  is  of  a  more  primitive 
type  and  is  usually  called  a  strobilus  or  cone.  The  carpels 
are  not  closed  around  the  seeds,  hence  there  is  no  ovulary, 
but  the  seeds  are  exposed  as  the  name  gymnosperm  implies. 
The  frequently  cultivated  Ginkgo  tree  is  the  lowest  type  of 
tree  growing  out  of  doors  in  our  region  and  has  leaves  that 
remind  one  of  the  leaflets  of  a  maiden-hair  fern.  It  is  the 
only  tree  we  have  that  is1  completely  flowerless.  The  stamens 
and  carpels  are  borne  in  rosettes  with  the  foliage  leaves  on 
dwarf  branches  which  continue  to  grow  from  year  to  year, 
often  for  a  long  time.  This  condition  is  therefore  similar 
to  what  is  present  in  the  tree  ferns,  the  plant  having  no 
determinate  axes  of  any  kind. 

Following  a  peculiar  process  known  as  the  reduction  divi¬ 
sion  which  takes  place  in  the  cells  inside  of  the  micro¬ 
sporangium,  a  considerable  number  of  microspores  are  de¬ 
veloped,  four  for  each  original  cell.  In  nearly  the  same 
wav,  four  .megaspores,  one  of  which  survives,  are  usually 
produced  in  each  ovule.  The  flowers  are  thus  modified  spore¬ 
bearing  branches  or  shoots  ,of  determinate  growth  producing 
two  kinds  of  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  sec¬ 
ondary  sexual  characters  and  dimorphisms.  The  microspores 
germinate  and  develop  into  the  pollen  grains  and  the  mega¬ 
spores  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. 


Field  Manual 


]() 

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 
sporophyte  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  plant  to  some  other  and  perhaps  more  favor¬ 
able  environment.  Here,  if  conditions  are  proper,  it  sprouts 
and  begins  its  life  as  an  independent  individual.  The  whole 
process  of  flower,  seed,  and  fruit  production  is  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,  subulate, 
or  scale-like;  conifers.  2. 

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

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

Ginkgo.  (1). 

2.  With  typical  dwarf  branches,  persistent  for  more  than 

one  year.  3. 

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

Taxodium.  (2). 

2.  Without  dwarf  branches.  4. 

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

leaves.  Pinus.  (7). 

3.  Drawf  branches  thick,  wart-like,  persisent,  with  numer¬ 

ous  deciduous  leaves.  Larix.  (6). 

4.  Leaf  buds  scaly;  leaves  scattered.  5. 

4.  Feaf  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). 

<V  Leaves  flat,  those  on  the  upper  side  of  the  twig  much 
shorter  than  the  lateral  ones;  trees.  Tsuga.  (4). 

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

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  acuta  than 
the  lateral  ones;  scales  of  the  carpellate  cone  6-10, 
not  peltate.  Thuja.  (8). 

(11) 


12 


Field  Manual 


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

Franked,  usually  much  elongated,  on  somewhat  flat¬ 
tened  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  cpiite 
similar;  scales  of  the  carpellate  cone  peltate. 

Chamaecyparis.  (10). 

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

opposite  or  in  threes;  the  seale-like  leaves  4-ranked, 
appressed,  causing  the  twigs  to  appear  quadrangu¬ 
lar,  the  subulate  leaves  spreading;  one  or  both  types 
of  leaves  on  a  plant;  carpellate  cone  developing  into 
a  bluish--black,  berry-like  fruit.  Juniperus.  (11). 


8.  Leaves  alternate.  9. 

8.  Leaves  opposite  or  whorled.  74. 

9.  Leaves  simple.  10. 

9.  Leaves  compound.  62. 

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

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

prominent  side  ribs  coming  from  near  the  base  of 
the  blade.  53. 

11.  Leaves  truncate  or  broadly  emarginate;  with  complete 

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

11.  Leaves  entire.  12. 

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

lobed.  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  taper¬ 

ing  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  pre¬ 

vious  season.  16. 

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

16.  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  peti¬ 

ole  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  stip¬ 

ules  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. 

Bundle  scars  2  or  more;  pith  without  lenticular  cavi¬ 
ties.  24. 


22. 


14 


Field  Manual 


23.  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  astrin¬ 
gent  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  la'teral  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  invo¬ 
lucre.  Castanea.  (55). 

29.  Usually  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  ere- 
nate-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  op  the  Northern  United  States 


15 


30.  Leaves  deeidely  inequilateral  at  the  base.  31. 

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

31.  Axillary  buds  prominently  stalked;  leaves  repand-den- 

tate.  Heamamelis.  (45). 

31.  Buds  sessile;  leaves  doubly  serrate,  bark  not  scaling 
off  in  plates.  Ulmus.  (48). 

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

like  in  the  Sycamore.  Planera.  (49). 

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  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  acuminate, 
sharply  double  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;  earpellate  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.  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.  (59). 

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  pubes¬ 
cent,  not  stellate;  fruit  a  nut-like  drupe. 

Symplocos.  (71). 

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

or  wedge-lanceolate.  Myrica.  (63). 

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

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

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

ily  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. 

44.  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  op  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  witli  typical  lateral  thorns,  but  some  may  have 

thorn-like  stunted  branches.  48. 

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

like  glands  on  the  petiole  or  at  the  base  of  the 

blade.  49. 

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

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

49.  Twigs  green,  red,  or  red  and  green;  nectar  glands  disc¬ 

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

Amygdalus.  (28). 

49.  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  ma¬ 

ture,  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. 

54. 
54. 


55. 

55. 

56. 


56. 

57. 

57. 

58. 

58. 

59. 


59. 


60. 

60. 

60. 

61. 

61. 


62. 

62. 

63. 


—  53  — 

Base  of  petiole  covering  the  axillary  bud;  twigs  with 
stipular  rings.  Platanus.  (47). 

Axillary  buds  usually  evident;  twigs  without  stipular 
rings.  54. 

Leaves  2-ranked.  55. 

Leaves  not  2-ranked.  60. 

Leaves  entire,  round-heart-shaped.  Cercis.  (29). 

Leaves  serrate,  dentate,  or  lobed.  56. 

Pith  usually  in  transverse  plates;  leaves  ovate-lance¬ 
olate,  inequilateral,  taper-pointed.  Celtis.  (50). 

Pith  solid,  not  diaphragmed.  57. 

With  milky  sap.  58. 

Without  milky  sap.  59. 

Twigs  gray  or  brown,  glabrous  or  nearly  so ;  leaves 
pubescent  or  glabrous  beneath.  Morus.  (51). 

Twigs  grayish-green,  downy;  leaves  tomentose  beneath. 

Papyrius.  (53). 

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

Leaves  inequilateral  at  the  base;  vascular  bundles  in 
base  of  petiole  several,  scattered.  Tilia.  (20). 

Leaves  more  or  less  star-shaped,  with  3-7  long  pointed 
serrate  lobes,  strongly  aromatic  when  crushed ;  pith 
5-angled.  Liquidambar.  (46). 

Leaves  entire  or  three-lobed,  bark  spicy-aromatic;  in¬ 
ternodes  very  unequal.  Sassafras.  (16). 

Leaves  crenate,  serrate,  dentate,  or  lobed,  not  star-shaped 
and  not  spicy-aromatic.  61. 

Pith  5-angled;  trees  usually  with  resinous  buds;  leaves 
usually  broad  based.  Populus.  (64). 

Pith  cylindrical  or  nearly  so;  usually  with  prominent 
typical  thorns.  Crataegeus.  (26). 

—  62  — 

Pith  diaphragmed.  with  cavities:  large  trees  with  pin¬ 
nate  leaves.  Juglans.  (62). 

Pith  not  diaphragmed.  63. 

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


'Treks  of  the  Northern  United  States 


19 


(33.  Leaves  evenly  pinnate  or  bipinnate;  axillary  buds  super¬ 
posed.  73. 

64.  Lobes  or  teeth  at  the  base  of  the  leaflets  with  promi¬ 
nent  green  glands  beneath;  leaves  pinnate,  very  large 
with  disagreeable  odor.  Ailanthus.  ( 19 ) . 

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

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

trees  or  shrubs.  66. 

65.  Leaflets  not  punctate.  67. 

66.  Leaves  pinnate,  with  stipular  spines.  Zanthoxylum.  (17). 

66.  Leaves  trifoliate,  without  stipular  spines;  bark  with 

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

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

the  petioles  and  stems  prickly;  sometimes  with  stipu¬ 
lar  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  mueronate,  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 

raehis  prominently  winged.  71. 

70.  Leaflets  serrate,  dentate,  or  lobed,  the  raehis  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  raehis  winged;  twigs  pubescent. 

Rhus.  (42). 

71.  Leaflets  not  inequilateral  or  only  slightly  so,  not  slender 
falcate;  raehis  not  winged;  twigs  glabrous. 

Toxicodendron.  (43). 


20 


Field  Manual 


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

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

cular  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  —  » 

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  den¬ 

tate,  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.  Fraxinus.  (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  mar¬ 

gin.  80. 

79.  Leaves  serrate,  eremite,  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). 

Leaves  not  lobed;  fruit  a  drupe.  Rhamnus.  (34). 


81. 


'Trees  of  the  Northern  United  States 


21 


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

82.  Leaves  entire.  85. 

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

in  base  of  petiole  1;  pith  rhombic.  Euonymus.  (35). 

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

or  nearly  so.  84. 

84.  Axillary  buds  sometimes  superposed;  leaves  finely  den¬ 

ticulate  ;  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;  vas¬ 
cular  bundles  in  the  base  of  petiole  3. 

Viburnum.  (83). 

84.  Axillary  buds  not  superposed;  leaves  serrate  with  stip¬ 

ules,  small;  bundle  scar  central;  twigs  brown,  some¬ 
times  with  thorns;  shrub-like  trees  with  drupe-like 
berries.  Rhamnus.  (34). 

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

vious  season.  Kalmia.  (67). 

85.  Leaves  deciduous  each  year.  86. 

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

with  the  midrib.  87. 

86.  Leaves  pinnately  veined  to  the  tip.  88. 

87.  Axillary  buds  not  covered  by  the  petiole  base ;  inflo¬ 

rescence  eymose.  Cornus.  (79). 

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

ers  in  involucrate  heads.  Cynoxylon.  (80). 

S8.  Stipules  none;  fruit  an  oblong  drupe. 

1  Chionanthus.  (73). 

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

Cephalanthiis.  (82). 


KEY  TO  THE  GENERA  OF  TREES  IN  THE 
WINTER  CONDITION 


Based  mainly  on  twig  and  stem  charcters.  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. 

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

Pinus.  (7). 

3.  Without  true  dwarf  branches.  4. 

4.  Leaf  buds  scaly.  5. 

4.  Leaf  buds  not  scaly,  naked.  7. 

5.  Leaf  scar  not  on  a  sterignia,  prominent,  circular;  leaves 

flat.  Abies.  (5). 

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

as  a  scale  on  the  twig.  (i. 

,6.  Leaves  flat,  those  on  the  upper  side  of  the  twig  much 
shorter  than  the  lateral  ones.  Tsuga.  '(4). 

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

Picea.  (3). 

7.  Foliage  leaves  small,  scalc-like,  appressed,  opposite,  4- 

ranked,  closely  covering  the  twigs  of  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  earpellate  cone  not 
peltate.  Thuja.  (8). 

7.  Foliage  leaves  small,  scale-like,  appressed,  opposite,  4- 
ranked,  usually  much  elongated,  on  somewhat  flat¬ 
tened  branches;  scales  of  the  earpellate  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  earpellate  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  seale-like  leaves  4-ranked, 
appressed,  causing  the  twigs  to  appear  quadrangu¬ 
lar,  the  subulate  leaves  spreading;  one  or  both  types 
of  leaves  on  a  plant;  carpellate  cone  developing  into 
a  bluish-black,  berry-like  fruit.  Juniperus.  (11). 

8.  Leaves  with  spine-tipped  lobes  or  teeth.  Ilex.  (36). 

8.  Leaves  without  spines.  9. 

9.  Leaves  pubescent  at  least  below,  lanceolate,  niucronate, 

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,  coria¬ 
ceous,  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  w'ith  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  branches,  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. 


24 


Field  Manual 


15.  Twigs  with  distinct  and  complete  stipular  ridges  or 
rings  at  the  leaf  nodes.  1(3. 

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  con¬ 
nate  stipules.  17. 

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

scars  oval  or  circular;  bark  spicv-aromatie. 

Liriodendron.  (13). 

17.  Buds  downy,  or  if  glabrous  then*  the  twigs  red:  pith 

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

Magnolia.  .  (12). 

18'.  With  thorns,  prickles,  or  spines;  or  with  spur-like 
branches  ending  in  thorns.  lib 

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

thorn-like  stunted  branches.  26. 

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

19.  Twigs  with  typical  lateral  thorns,  without  terminal 

thorns.  21. 

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

19.  Stems  or  twigs  with  prickles;  leaf  scar  extending  nearly 

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

20.  Leaf  scar  covering  the  two  or  more  superposed  axillary 

buds.  Robinia.  (33). 

20.  Leaf  scar  below  the  axillary  buds;  buds  reddish,  pubes¬ 

cent.  Zanthoxylum.  (17). 

121.  With  thorns  beside  the  axillary  buds;  normally  one  for 
each  leaf  axil,  becoming  gradually  smaller  toward  the 
tip  of  the  twig,  terminal  bud  absent.  Toxy’.on.  (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 

tlie  leaf;  leaf  scar  covering  the  two  or  more  super¬ 
posed  axillary  buds ;  twigs  polished,  often  zigzag. 

Gleditsia.  (30). 

22.  Not  with  three  distinct  bundle  scars.  23. 

22.  With  three  bundle  scars.  24. 

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

Rhamnus.  (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  <|uite  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,  soljd;  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  numer¬ 

ous  dry  scales.  Fagus.  (54). 

30.  Winter  buds  rather  Meshy,  usually  with  1-3  visible  scales. 

Tilia.  (29). 


i('ield  Manual 


26 

31. 

31. 

31. 

32. 


32. 


33. 


33. 

34. 


34. 


35. 


36. 


37. 


37. 


57. 


Pith  5-angled,  twigs  glabrous  or  somewhat  pubesc.no, 
reddish  or  yellowish-brown.  Castanea.  (50). 

Pith  cylindrical;  visible  bud  scales  more  than  3;  twigs 
glabrous  or  pubescent  but  not  downy.  Moras,  (oi/. 

Pith  cylindrical;  visible  bud  scales  x-o,  twigs  downy, 
grayish-green,  bark  very  fibrous.  Papyrius.  (o3j. 

Pith  interruptedly  diaplnagmed,  with  •  cavities,  smau, 
greenish-white.  Celtis.  (50). 

Pith  solid.  33. 

Terminal  bud  naked,  elongated,  tomentose;  buds  promi¬ 
nently  stalked,  light  gray ;  twigs  zigzag. 

Hamamiis.  .(15,). 

Terminal  bud  absent,  the  twig  showing  a  terminal  selr- 
pruning  scar  at  the  morphological  tip;  or  if  present 
then  with  scales ;  buds  not  stalked.  31. 

Terminal  bud  present,  long  pointed;  leai  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). 

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). 


'Trees  of  the  Northern  United  States 


27 

37.  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.  4(5. 

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. 

40.  Pith  large,  brown;  twigs  thick,  with  large  leaf  sears  and 

3  prominent  bundle  scars.  Juglans.  (62). 

40.  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.  ( B 1 )  - 

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

Ptelea.  (18). 

42.  Leaf  scar  covering  the  axillary  buds;  pith  small;  twigs 

brown,  polished,  often  zigzag.  Gleditsia.  (50). 

43.  Pith  cylindrical  or  nearly  so.  44. 

43.  Pith  more  or  less  5-angled,  yellowish  or  brownish;  ter¬ 

minal  bud  large;  bundle  scars  scattered;  trees  with 
tough  twigs.  Hicoria.  (61). 

44.  Leaf  scar  surrounding  the  hairy  axillary  buds;  bundle 

scars  5-9;  terminal  bud  self-pruned.  Cladrastis.  (32), 

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

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

scars  heart-shaped;  stipular  scars  none. 

Sapindus.  (38) 


28 


Field  Manual 


45.  Bundle  sear  usually  1 ;  buds  rounded  or  somewhat 

pointed;  stipular  sears  or  minute  stipules  present. 

Ilex.  (30) . 

—  46  — 

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

staminate  and  earpellate  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  resin¬ 
ous;  pith  large.  Rhus.  (42). 

47.  Leaf  sears  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  present;  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  aromatic; 

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  per¬ 
sisting  all  winter.  Oxydendrum.  (68). 

53.  With  2  visible  scales  in  the  triangular  flattened  bud; 
pith  sometimes  with  cavities;  twigs  pubescent;  zigzag 
at  the  tip.  Diospyros.  (70). 


TlCKKH  OH’  'I'll IC  Noktiikrm  IJNITKI)  Status 


29 


54.  Outer  IiikI  scales  more  thmi  l.  55. 

54.  Outer  bud  scale  1;  twigs  iinually  with  brittle  zones  and 

lienee  very  easily  detached;  stipular  sears  present; 
bundle  sears  4;  pitli  small.  Salix.  (05). 

55.  i’ith  diaphragmed  but  solid;  bundle  scars  4;  no  stip- 

ular  sears.  Nyssa.  (81). 

55.  I’ith  not  diaphragmed.  50. 

50.  I’ith  more  or  less  5-angled.  57. 

50.  I’ith  cylindrical  or  nearly  so.  01. 

57.  Huds  clustered  at  the  tip  of  the  twig;  bundle  sears  nu¬ 
merous,  scattered.  Quercus.  (50). 

57.  Huds  not  clustered  at  the  tip.  58. 

58.  Hundle  sears  numerous,  usually  scattered.  59. 

58.  Hundle  sears  4.  00. 

59.  Hulls  small  with  about  4  outer  scales;  twigs  reddish 

or  yellowisb-biown,  glabrous  or  pubescent;  terminal 
bud  present  or  absent;  stipular  sears  prominent. 

Castanea.  (55). 

59.  Terminal  bud  large  with  4  or  more  visible  scales,  hairy 
or  peltate  pubescent;  lateral  buds  usually  superposed; 
twigs  tough.  Hicoria.  (01). 

0(1.  Without  stipular  or  self-pruning  sears;  crushed  buds 
fragrant,  aromatic,  not  resinous,  glabrous. 

Liquidambar.  (40). 

(10.  Stipular  and  self-pruning  sears  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.  (04). 

01.  I’ith  very  large,  light  , brown,  bark  nut  resinous,  ill¬ 
smelling;  buds  spherical  or  flattened  at  the  apex, 
often  clustered  at  the  tip  of  the  twig,  brown  and 
pubescent;  bundle  sears  about  9  along  the  lower 
edge  of  the  very  large  leaf  sear;  large  trees. 

Ailanthus.  (19). 

01.  I’ith  small,  or  if  large  and  brown  then  the  bark  resin¬ 
ous.  02. 

02.  Ifaik  with  a  resinous  or  sticky  milky  sap;  pith  usually 
large,  if  rather  small  then  the  bark  aromatic.  03. 


30 


Pield  Manual 


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  sears  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  gladular; 

bundle  scars  3.  Prunus.  (27). 

66.  Buds  not  clustered  at  the  tip;  twigs  not  gladular; 

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  pubescent, 

gray  or  brown.  Rhamnus.  (34). 

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

very  unequal;  lateral  buds  minute;  small  trees. 

Cornus.  (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). 

70.  Buds  rounded  at  the  apex;  scales  thick;  twigs  often 
zigzzag;  plant  usually  with  some  thorns,  not  gland¬ 
ular  dotted.  Crataegus.  (26). 


'Trees  of  the  Northern  United  States 


31 


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  pu¬ 
bescent  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  ellipse  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  diamond¬ 

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. 

76.  Axillary  buds  often  superposed;  twigs  often  with  thorns; 

leaf  scars  small.  Forestiera.  (75). 


Field  Manual 


Axillary  buds  not  superposed;  no  thorns  on  the  twigs; 
leaf  sears  rather  large.  77. 

Twigs  and  buds  pubescent;  lateral  buds  cylindrical  or 
hemispherical;  bud  scales  dry;  leaf  scar  concave,  on 
the  short  petiole  base ;  lenticels  large  and  conspicu¬ 
ous;  fruit  a  drupe.  Chionanthus.  (73). 

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


Fraxinus.  (74). 

Axillary  buds  minute  and  sunken;  twigs  glabrous  or 
pubescent;  stipules  dry,  prominent;  or  with  promi¬ 
nent  stipular  scars.  Cephalanthus.  (82). 

With  4  distinct  stipular  scars;  terminal  bud  self -pruned ; 
twigs  green  with  strong  odor.  Staphylea.  (37). 

Without  definite  stipular  scars;  twigs  not  green  or  if 
so  then  the  terminal  bud  present.  79. 

Trees  or  shrubs  with  numerous  bundle  scars, 
in  3  areas,  in  a  large  heart-shaped  leaf 


rather  large;  terminal 
scales.  Aesculus.  (40). 
Bundle  scars  3  or 


sometimes 
scar ;  pith 
bud  large,  with  numerous 


5.  80. 


sometimes 

Terminal  bud  with  2  long  acuminate  pubescent  outer 
scales;  line  connecting  the  uppermost  leaf  scars 


notched.  81. 

Terminal  bud  with  one  main  pair  of  visible  scales  and 
a  smaller  pair  at  the  base.  Viburnum.  (83). 
Terminal  bud  with  several  pairs  of  visible  scales; 
bundle  scars  3-5;  twigs  sometimes  green. 


Acer.  (41). 

Axillary  buds  usually  minute  and  undeveloped  except 
at  the  base  of  the  peduncle  which  is  self-pruned; 
twigs  green  or  reddish-green,  glabrous  or  nearly  so. 

Cynoxylon.  -(80). 

Axillary  buds  normally  well  developed  and  prominent; 
twigs  often  very  pubescent.  Cornus.  1791 . 


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  directly 
on  the  micropyle  of  the  ovule  which  is  mostly  with¬ 
out  a  pollen-chamber;  trees  or  shrubs;  ours  usually 
evergreen  with  narrow  leaves;  monecious,  rarely  die- 
cious.  2. 

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

with  a  stigma  for  the  reception  of  the  pollen ;  flow¬ 
ers  more  commonly  showy.  4. 

2.  Leaves  fansliaped,  dichotomously  veined,  on  thick  wart¬ 

like  dwarf  branches;  dieeious  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  form¬ 
ing  a  black  or  blue  berry-like  fruit;  leaves  opposite 
or  whorled,  rarely  scattered,  persistent.  Junipekaceae. 
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  upper  fertile.  Thuja.  (8). 

b.  Cone  scales  4-6,  the  2  upper  fertile.  Libocedrus.  (9). 

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

Chamaecyparis.  ( 10 ) . 

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

Juniperus.  (11). 


(33) 


Field  Manual 


14 

3.  Leaf-buds  scaly;  carpels  usually  numerous;  leaves 

spirally  arranged,  the  foliage  leaves  often  situated 
on  dwarf  branches.  Pinaceae. 

a.  Without  dwarf  branches.  b. 

a.  With  dwarf  branches.  d. 

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

scales  representing  the  leaf  bases.  c. 

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

leaves  usually  flat;  earpellate  cones  erect. 

Abies.  (5). 

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

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

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

shorter  than  the  lateral  ones;  earpellate  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  (tetramer- 
ous)  ;  cotyledons  usually  2;  vascular  bundles  usually 
in  a  circle  around  a  central  pith,  forming  annual  rings 
of  growth  in  perennial  stems,  with  hark  on  the  out¬ 
side.  5. 


'Trees  of  the  Northern  United  States 


35 


5.  DICOTYLAE. 

5.  Perianth  none  or  of  similar  segments  or  divided  into 
calyx  and  corolla;  corolla  when  present  clioripetalous 
(petals  distinct),  sepals,  petals  and  stamens  some¬ 
times  on  a  disk  or  hypanthium.  6. 

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

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

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

7. 

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

or  colored;  or  perianth  none.  25. 

7.  Flowers  liypogynous  or  perigynous;  ovulary  free  or 

only  slightly  adherent  to  the  perigynous  disk  or  hy¬ 
panthium.  8. 

7.  Flowers  epigynous  or  apparently  epigynous ;  calyx  above 

the  ovulary,  with  or  without  an  hypanthium.  24. 

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

than  twice  the  petals.  9. 

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

8.  Stamens  of  the  same  number  as  the  petals  and  oppo¬ 

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

Rhamnaceae. 

a.  Rhamnus.  (34). 

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

be  several.  10.  > 

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

Anonaceae. 

a.  Asimina.  (14). 

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


36  Field  Manual 

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  mu¬ 
cilaginous.  Tiliaceae. 

a.  Tilia.  (20). 

11.  Flowers  not  subtended  by  a  membranous  bract;  leaves 

alternate  with  deciduous  stipules;  sepals  persistent. 
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  punctate  with  pellucid  dots,  alternate.  Rutaceae. 

a.  Zanthoxylum.  (17). 

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

disk-like  glands  under  the  teeth  or  lobes.  Sima- 
rubaceae. 

a.  Ailanthus.  (19). 

15.  Carpel  1,  ovulary  with  1  parietal  placenta;  leaves  alter¬ 

nate,  usually  with  stipules;  usually  compound.  Faba- 

CEAE. 


'Tkees  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  imperfectly 

diecious.  b. 

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

Gleditsia.  (30). 

b.  Stamens  10;  pith  large,  chocolate-colored;  with¬ 
out  thorns;  Gymnocladus.  (31). 

B.  Upper  petal  inclosing  the  lateral  ones  in  the  bud; 

leaves  compound  (sometimes  with  1  leaflet)  with 
stipules.  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  ovul- 

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

16.  Ovulary  2-loeular  to  pluriocular.  17. 

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

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

a.  Leaves  simple;  style  lateral.  Cotinus.  (44). 

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

the  rachis  wing-margined;  not  poisonous. 

1  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.  Aesctjlaceae. 


38 


Field  Manual 


a.  Aesculus.  (40). 

17.  Flowers  irregular  in  the  number  of  the  several  floral 

sets ;  leaves  pinnate  or  bipinnate, .  alternate ;  ovulary 
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. 

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

shrubs  with  opposite  pinnate  or  simple  leaves.  Olea- 
ceae. 

a.  Flowers  diecious,  from  catkin-like  scaly  buds. 

Forestiera.  (75). 

a.  Flowers  bisporangiate,  petals  linear. 

Chionanthus.  (73). 

19.  Stamens  more  numerous  than  the  petals;  leaves  pal- 

mately  veined,  opposite;  fruit  2-wi:tged.  Some  Acer- 
ACEAE. 

a.  Acer  (41). 

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

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

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

a.  Staphylea.  (37). 

21.  Leaves  palmately  veined,  or  compound.  22. 

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

22.  Leaves  pinnately  compound,  alternate;  our  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.  Acer- 
aceae. 

a.  Acer'.  (41). 

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


'Trees  of  the  Northern  United  States 


39 


a.  Ptelea.  (18). 

23.  Calyx  minute;  trees  or  shrubs  with  simple  mostly  alter¬ 
nate  leaves.  Ilicaceae. 


a.  Ilex.  (36). 

23.  Calyx  not  minute;  trees,  shrubs,  or  woody  climbers; 

ours  with  opposite  leaves  and  with  minute,  fugaceous 
'Stipules.  Cei.astraceae. 

a.  Euonymus.  (35). 


—  24  — 

24.  Perfect  stamens  4,  styles  2;  leaves  alternate,  palmately 
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.  (Malatae). 
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). 
e.  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  leath¬ 
ery.  e.  , 

e.  Leaves  sharply  and  regularly  serrate,  glabrous  when 

mature,  petioles  long;  pome  with  grit  bells. 

Pyrus.  (22). 

e.  Leaves  irregularly  dentate  or  serrate,  or  more  or  less 
lobed;  pome  without  grit  cells.  Malus.  (23). 
24.  Stamens  4  or  5,  style  and  stigma  1  ;  leaves  opposite  or 
alternate.  Cornaceae. 

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


40 


Field  Manual 


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  disk  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.  Arali- 

aceae. 

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.  (4}). 

26.  Stamens  2-4;  leaves  pinnately  veined  when  simple,  or 

if  pinnately  compound  then  the  axillary  buds  exposed. 
Oleaceae. 

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

Fraxinus.  (74). 

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

Forestiera.  (75). 

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

spikes  or  spherical  heads.  31. 

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

28.  With  prominent  stipular  spines;  leaves  punctate  with  • 

glands.  Rutaceae. 

a.  Zanthoxylum.  (17). 

28.  Without  stipular  spines.  29. 

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. 


Trees  of  the  Northern  United  States 


41 


a.  Rhamnus.  (34). 

29.  Styles  or  stigmas  2;  leaves  2-ranked;  ovulary  1-2- 
ovuled;  stipules  fugaceous.  Ulmaceae. 
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  evergreen. 

Persea.  (15). 

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

Sassafras.  (16). 

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

See  15  above. 

30.  Calyx  5-parted;  stamens  5-15;  dowers  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). 

32.  Axillary  buds  not  superposed  or  if  so  then  the  stam¬ 
inate  flowers  not  in  flexible  catkins;  leaves  sim¬ 
ple.  33. 


42 


Field  Manual 


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  aiid  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  twro  prominent  lateral 

veins  from  the  base  or  if  not  then  the  t wigs  thorny. 
Moraceae. 

a.  Twigs  wdth  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  carpel- 
late  capitate.  Papyrius.  (53). 

35.  Sap  not  milky.  36. 

36.  Both  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.  (55). 
b.  Carpellate  flower  1  in  each  involucre,  which  con¬ 
sists  of  numerous  scales.  Quercus.  (56). 

37.  Ovulary  1-locular,  many  seeded;  seeds  with  a  tuft  of 

cottony  hairs.  Salicaceae. 


Trees  oe  the  Northern  United  States 


43 


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

Populus.  (64). 

a.  Stamens  2-1U;  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  clus¬ 
tered  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  twig.  Betulaceae. 
a.  Pith  3-angled;  buds  stalked;  leaves  not  2-ranked; 

stamens  4.  A'lnus.  (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  — 

I 

39.  Flowers  liypogynous  (ovulary  superior).  40. 

39.  Flowers  epigynous  (ovulary  inferior).  44. 

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

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

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


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  an¬ 
thers  at  first  held  in  the  little  sacs.  Kalmia.  (67). 

41.  Choripetalous  plants  in  which  the  petals  are  sometimes 

partly  or  completely  united, 
a.  Ovulary  1 -locular  (1  carpel)  with  1  parietal  placenta. 
Fabaceae. 

See  15  above. 

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

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,  zvg'omorphic ;  seeds  numerous,  sta¬ 
mens  4,  didynamous ;  pith  with  cavities.  Some 
— Scrophulariaceae. 

a.  Paulownia.  (76). 

43.  Flowers  irregular,  zyiromorphic ;  seeds  numerous,  fertile 
stamens  usually  2  with  3  vestiges;  pith  solid.  Big- 
noniaceae. 


Trees  of  the  Northern  United  States 


45 


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.  Rubiaceae. 

a.  Cephalanthus.  (82). 

46.  Usually  without  stipules;  flowers  in  compound  cymes 
in  our  species;  not  blackening  in  drying.  Capri- 
foi.iaceae. 

a.  Viburnum.  (83). 


CLASSIFICATION  AND  DESCRIPTION  OF  THE 
SPECIES. 


SPERMATOPHYTA.  SEED-PLANTS. 

Phylum,  CYCADOPHYTA. 

Class,  Ginkgoae. 

Order,  Ginkgoales. 

Ginkgoaceae.  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  diecious  tree.  Seed  large,  drupe-like.  Autumn 
leaves  orange.  Introduced  from  China  and  Japan;  should  be 
commonly  cultivated  for  ornament. 

Phylum,  STROBILOPHYTA. 

Class,  Coniferae.  Conifers. 

Order,  Pinales. 

Taxodiaceae.  Bald-cypress  Family. 

2.  Taxodium  Rich.  Bald-cypress. 

Trees  with  feather-like,  annually  deciduous  (ours)  dwarf 
branches  with  the  numerous,  small,  narrow  leaves  usually 
spreading  into  two  ranks,  and  having  the  slender  twigs  cov¬ 
ered  with  small  self-pruning  scars. 

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

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

(46) 


Trees  oi"  the  Northern  United  States 


47 


Pinaceae.  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  cylin- 
dric.  2. 

1.  Twigs  pubescent,  brown;  carpellate  cones  ovoid  or  oval. 

3. 

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

long.  P.  abies. 

2.  Leaves  usually  not  much  over  l  in.  long;  very  glau¬ 

cous;  carpellate  cones  f-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  sea'- 
sons.  P.  mariana. 

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

2.  Picea  canadensis  (Mill.)  B.  S.  P.  White  Spruce. 
A  slender  tree  sometimes  with  a  strong  skunk-like  odor. 
Leaves  light  green,  slender,  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  Alleglianies  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; 


48 


.Field  Manual 


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  fiat  linear  leaves,  those  on  the  top 
of  the  twig  short,  and  having  the  twigs  covered  with  ster- 
igma-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  ovuliferous 
scale  or  but  little  longer;  leaves  obtuse.  A.  bal- 
samea. 

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


Trees  of  the  Northern  United  States 


49 


(5.  Larix  (Tourn.)  Adans.  Larch. 

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

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

1.  Carpellate  cones  small,  J-f  in.  long,  oval  or  almost 
globular;  ovuliferous  scales  glabrous;  native,  grow- 
in  bogs  and  wet  ^places.  L.  laricina. 

1.  Carpellate  cones  rather  large  1-1 J  in.  long;  ovuliferous 
scales  finely  tomentose  on  the  back,  cultivated  in  dry 
ground.  L.  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  beautiful 
tree  with  horizontal  branches  and  drooping  branchlets,  conical 
in  shape  when  young;  much  cultivated  in  some  parts  of  the 
United  States.  The  source  of  Venice  turpentine.  Native  of 
Europe. 

7.  Pinus  (Tourn.)  L.  Pine. 

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

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

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

them  may  be  with  3.  5. 


50 


Field  Manual 


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  %-l  in.  long;  leaves 

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

4.  Old  sheaths  about  j  in.  long;  leaves  glaucous;  car-  ' 

pellate  cones  ovoid.  P.  serotina. 

5.  Twigs  glaucous;  resin-ducts  parenchymatous;  carpel¬ 

late  cones  1J-3  in.  long;  ovuliferous  scales  with  a 
prickle  or  small  spine.  6. 

5.  Twigs  not  glaucous.  7. 

6.  Leaves  slender,  2J-5  in.  long;  buds  not  very  resinous; 

prickles  of  the  ovuliferous  scales  short  and  small.  P. 
ecMnata. 

6.  Leaves  stout,  1J-2J-  in.  long;  buds'  very  resinous; 

prickles  of  the  ovuliferous  scales  long  and  stour.  P. 

virginiana. 

7.  Leaves  1-4  in.  long,  grayish-green  or  light' green;  ovul¬ 

iferous  scales  without  or  with  a  small  prickle,  or  with 
a  thiek  point  or  spine.  9. 

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

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

8.  Foliage  lustrous,  resin  ducts  peripheral;  carpellate 

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

8.  Foliage  dull;  resin  ducts  parenchymatous;  carpellate 

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

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

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

9.  Leaves  ,  in.  long.  10. 

10.  Leaves  1J-2J  in.  long,  grayish-green; twigs  dull  green¬ 
ish-yellow  or  greenish-brown ;  resin  ducts  peripheral ; 
carpellate  cones  ovate-conic,  2-3  in.  long.  P.  nil- 
veftrio. 


Trees  op1  the  Northern  United  States 


51 


10.  Leaves  \-l\  in.  long;  resin  ducts  parenchymatous;  car- 
pellate  cones  oblong-conic,  1-2  in.  long,  usually  up¬ 
wardly  curved.  P.  banlcsiana. 

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  Iowa. 

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

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  rigida  Mill.  Pitch  Pine.  A  tree  with  spread¬ 
ing  branches,  the  old  bark  rough  and  furrowed,  flaky  in  strips. 
Sprouts  readily  from  the  stump  if  cut  down  or  burned.  Wood 
rather  hard  and  brittle  and  full  of  resin;  used  for  fuel,  char¬ 
coal,  and  coarse  lumber.  A  source  of  turpentine  to  a  limited 
extent.  Tn  dry,  sandy  or  roeky  soil.  N.  B.  to  Ont.,  ITnn., 
Ohio,  W.  Va.  and  Ga. 

5.  Pinus  resinosa  Ait.  Red  Pine.  A  tall  tree  with  i  ed¬ 
dish  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. 

6.  Pinus  lari'cio  Poir.  Austrian  Pine.  A  tall,  open,’ 
pyramidal  tree  of  rapid  growth  with  the  thick  spreading 
branches  in  regular  whorls.  Often  cultivated.  From  Europe1. 

7.  Pinus  stives' tr  is  L.  Scotch  Pine.  A  large  and  valu¬ 
able  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 


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  valuable;  much  used  as  lumber. 
Also  furnishes  some  turpentine.  Produces  shoots  from  stumps. 
In  sandy  soil.  N.  Y.  to  Fla.,  Ohio,  Ill.,  Okla.,  and  Texas. 

10.  Pinus  pungens  Lamb.  Table-mountain  Pine.  A  tree 
with  spreading  branches,  the  old  bark  rough  and  in  flakes, 
leaves  sometimes  in  3’s.  Wood  light  and  soft;  much  used  for 
charcoal.  N.  .1.  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  Tnd. 

Juniperaccae.  Juniper  Family. 

Subfamily,  Cupressalae. 

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.  Occidentalis. 

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  occidentalis  L.  American  Arborvitae.  Usually 
a  small  conical  tree  with  fan-like  branches.  Self-prunes 


Trees  oe  the  Northern  United  States 


53 


twigs.  Wood  light  and  durable;  used  for  posts,  railroad  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  pyra¬ 
midal  or  bushy  tree  with  spreading  and  ascending  branches. 
Native  of  Asia.  Cultivated  in  many  forms.  Probably  be¬ 
longs  to  a  distinct  genus,  Biota  Endl. 

9.  Libocedrus  Endl.  Incense-cedar. 

Evergreen  trees  with  naked  buds  and  small,  scale-like, 
appressed,  opposite,  4-ranked,  usually  elongated  leaves  on 
somewhat  flatened  branches;  scales  of  the  earpellate  cone  4-6, 
the  two  upper  fertile,  not  peltate. 

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

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

10.  Chamaecyparis  Spacli.  White-cedar. 

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

Monecious ;  earpellate  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  to  N.  H.  to  N.  .T.,  Fla.,  and  Miss. 

2.  Chamaecyparis  lawsoniana  (Murr.)  Pari.  Lawson  Cy¬ 
press.  A  large  tree  with  an  abruptly  enlarged  base  and  a 
spire-like  crown  of  small  horizontal  or  pendulous  branches. 


54 


Field  Manual 


Bark  often  10  in.  thick.  Wood  light,  hard,  and  strong, 
abonuding  in  fragrant  resin.  From  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  eone-s  developing  into  a  bluish-black  berry-like  fruit. 

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

1.  Leaves  all  subulate,  prickly  pointed,  verticillate,  slender, 

,  mostly  straight;  cones  axillary.  J.  communis. 

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

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

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

Phylum,  ANTHOPHYTA. 

Class,  Dicotylae.  Dicotyls. 

Subclass,  Thalamiflokae. 

Order,  Ranales. 

Magnoliaceae.  Magnolia  Family. 

12.  Magnolia  L.  Magnolia. 

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


Trees  of  the  Northern  United  States 


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

1.  Leaves  auriculate,  glabrous.  Leaf  buds  glabrous.  '  M. 
fraseri. 

1.  Leaves  rounded  or  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.  tripetala. 

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  oi 
somewhat  acuminate,  rounded  or  truncate  at  the  base,  J-l  ft. 
long;  flowers  greenish-yellow.  Wood  soft,  light,  and  durable; 
used  for  cabinet-work,  pump-logs,  and  water-troughs.  N.  \ . 
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  Texas. 

4.  Magnolia  fraseri  Walt.  Fraser  Magnolia.  A  tree  with 
spreading  branches  and  glabrous  leaf  buds.  Leaves  clon- 
gated-obovate  or  oblong,  auriculate,  J-2  ft.  long;  flowers  white. 
In  mountain  woods.  Va.  and  Ky.  to  Fla.  and  Miss. 

Various  Magnolias  are  ip  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. 


Field  Manual 


56 


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

1.  Liriodendron  tulipifera  L.  Tuliptree.  A  very  large 
magnificent,  rapid-growing  tree  with  glabrous  leaf -buds.  Flow¬ 
ers  greenish-yellow,  orange-colored  within.  Autumn  leaves  pure 
yellow.  Next  to  the  Sycamore,  probably  the  largest  tree  in 
the  Northeastern  United  States;  trunk  sometimes  34  feet  in 
cireumfercence.  Wood  light,  soft,  and  straight-grained,  easily 
worked;  heart  wood  light  yellow  or  brown;  sapwood  thin, 
nearly  white.  Used  for  interior  finish,  shingles,  boat-build¬ 
ing,  panels  of  carriages,  wooden  pumps,  wooden  ware  of 
various  kinds,  wood  pulp,  furniture,  implements,  boxes,  shelv¬ 
ing,  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. 

Anonaoeae.  Custard-apple  Family. 

14.  Asimina  Adans.  Papaw. 

Trees  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 ;  carpels  3-15. 

1 .  Asimina  triloba  (L.)  Dunal.  Papaw.  A  small  tree 
or  shrub  with  smooth  dark  bark  and  nodding  young  twigs.  Flow¬ 
ers  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  rover  bottoms  and  on  hillsides. 
Ont.  and  N.  Y.  to  Mich.,  Neb.,  Tex.,  and  Fla. 

Lauraceae.  Laurel  Family. 

15.  Persea  (Plum.)  Gaertn.  Bay. 

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

Perianth  fi-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 


57 


puberulent  or  nearly  glabrous  leaves.  Wood  hard,  strong, 
bright  red  in  color,  and  rather  brittle;  used  for  cabinet-making 
and  interior  finish.  Along  streams  and  the  border  of  swamps. 
Del.  to  Fla.,  Ark.,  and  Texas. 

16.  Sassafras  Nees  and  Eberm.  Sassafras. 

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

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

1.  Sassafras  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.  The  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  Texas. 

Order,  Geraniales. 
liutaceae.  Rue  Family 

17.  Zanthoxylum  L.  Prickly-asli. 

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  Ya.,  Ontario,  S.  Dak.  and  Kan. 


18.  Ptelea  L.  Hoptree. 

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

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

ular. 


58 


Field  Manual 


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

Siniarubaceae.  Ailanthus  Family. 

19.  Ailanthus  Desf.  Ailanthus. 

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

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

1.  Ailanthus  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  use¬ 
ful.  '  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. 

Tiliaceae.'  Linden  Family. 

20.  Tilia  (Bourn.)  L.  Linden. 

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

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

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

1.  Leaves  glabrous  above,  pubescent  beneath.  T.  pubes- 
cens. 

1.  Leaves  glabrous  above,  silvery- white  beneath.  T.  hcte.ro- 

phylla. 

2.  Petals  with  scales  at  the  base;  inflorescence  without 

bracts;  leaves  comparatively  large;  native.  T. 
amerieana. 


Trees  of  the  Northern  United  States 


59 


2.  Petals  without  scales  at  the  base;  inflorescence  with 
large  bracts;  leaves  comparatively  small;  cultivated. 
T.  exiropaea. 

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  6a.,  Mani¬ 
toba,  Kan.,  and  Texas. 

2.  Tilia  pubescens  Ait.  Downy  Linden.  A  small  tree 
growing  in  moist  soil,  mostly  along  the  coast.  A  ood  as  in 

americana  but  lighter  in  weight.  Va.  to  Fla.,  west  to  lex. 

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  oiigin  of 
the  family  name  of  Linnaeus.. 

Subclass,  Caivyciflorae. 

Order,  Rosales. 

Jlonaceae.  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  narrow 
leaf  scar. 

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

1.  Leaflets  glabrous  above.  2. 

1.  Leaflets  pubescent  on  both  sides;  calyx  and  pedicels 

usually  woolly.  S.  aucuparia. 

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

eter.  S.  americana. 

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

in  diameter,  o.  scopulina. 


60 


Field  Manual 


I.  Sorbus  americana  Alarsh.  American  Mountain-ash. 
A  small  tree  with  smooth  bark.  Bark  and  unripe  fruit  very 
astringent.  Wood  soft,  light  brown.  In  moint  ground.  Much 
prized  for  ornamental  planting.  Newf.  to  Alan.,  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-asli.  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. 

1  rees  or  shrubs  with  alternate,  simple,  pinnately-veincd, 
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  slen¬ 
der  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.  .T. 
and  Ohio. 


23.  Malus  Mill.  Apple,  Crab-apple. 

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

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

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

L  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.  glaucescens. 


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  eordate  at  the  base;  pome  usually 
large,  2-4  in.  in  diameter.  M.  malm. 

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.  Pedicles  very  slen¬ 
der  ;  fruit  small,  not  becoming  mellow.  Cultivated. 

3.  Malus  glaucescens  Relid.  Fragrant  Crab-apple.  A 
small  tree  with  hard  and  sour  fruit  suitable  for  preserving. 
Leaves  ovate,  to  triangular-ovate,  sparingly  pubescent  beneath 
when  young,  sharply  serrate  and  often  somewhat  lobed.  Wood 
soft  and  reddish-brown.  On  low  ground.  Ont.  to  Mich., 
S.  Car.,  Iowa,  and  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  be¬ 
neath.  Fruit  large,  varioufe.  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. 


(32 


Field  Manual 


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  sear,  and  fruit  a  berry-like  pome. 

Flower  bisporangiate,  perianth  pentamerous,  pome  small 
with  twice  the  number  of  cavities  as  styles. 

1.  Leaves  acute  or  acuminate  at  the  apex;  top  of  the 
ovulary  glabrous  or  nearly  so.  2. 

1.  Leaves  rounded,  obtuse  or  subacute  at  the  apex;  top 

of  the  ovulary  woolly;  petals  J-f  in.  long.  A.  san¬ 
guined. 

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  Juneberry. 
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  June¬ 
berry.  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  t.ypiical  axil¬ 
lary  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  unsatis¬ 
factory  condition.  Probably  many  of  those  included  below 


Trejgs  of  the  Northern  United  States 


63 

are  merely  hybrids  or  forms  of  freely  interbreeding  elementary 
varieties.  Many  of  the  specific  English  nuames  the  also 
unsatisfactory. 

Required  for  identification,  the  leaves  and  fruit. 

1.  Leaves  not  deltoid-cordate.  2. 

1.  Leaves  conspicuously  deltoid-cordate,  glabrous.  ((  or 

datae) .  55. 

2.  Leaves  glabrous,  glabrous  above  and  pubescent  beneath, 

or  pubescent  on  both  sides.  3. 

2.  Leaves  pubescent  above,  glabrous  beneath;  thorns  1-1  in. 

long;  fruit  black.  (Douglasianae) .  54. 

3  Petioles  1  in.  long  or  longer.  4. 

3.  Petioles  less  than  V4  in.  long.  (Parvifoliae).  53. 

4.  Leaves  not  deeply  cut.  5. 

4.  Leaves  deeply  cut,  lobes  numerous;  thorns  less  than  1 

in.  long.  (Oxyacanthae.).  52. 

5.  Leaves  broadest  at  the  middle  or  apex,  cuneate.  6. 

5.  Leaves  broadest  at  the  base.  12. 

6.  Leaves  broadest  toward  the  apex.  7. 

6.  Leaves  broadest  at  the  middle,  s. 

7.  Leaves  shining  not  impressed-veined  above.  (Crus- 

galli) .  14. 

7.  Leaves  dull,  impressed-veined  above.  (Punctata^).  18. 
S.  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.  (Tntri- 
catae).  30. 

9  Calyx-lobes  glandular-laeiniafo,  glandular-serrate,  or 
glandular-margined.  10. 

9.  Calyx-lobes  not  glandular-margined ;  leaves  not  im¬ 

pressed-veined,  often  trilobed  towards  the  apex. 
(Virides).  29. 

10.  Leaves  impresSed-veined.  11. 

10.  Leaves  not  impressed-veined,  elliptic  ovate  to  orbicular: 

calyx-lobes  glandular-margined;  leaves  not  trilobate 
(Rotundi  foliae) .  24. 

11.  Leaves  rhombic-elliptic;  calyx-lobes  usually  deeply  cut; 

nutlets  deeply  pitted  on  the  ventral  faces.  (Maera 
canthaej.  21. 


64 


Field  Manual 


11.  Leaves  elliptic  to  ovate;  calyx-lobes  less  deeply  cut;  nut¬ 

lets  with  shallow  pits  on  the  ventral  faces.  (Brain- 
erdianae).  23. 

12.  Leaves  §-2J  in.  long  and  wide,  membranous;  calyx-lobes 

usually  entire.  13. 

12.  Leaves  1-4  in.  long  and  wide;  calyx-lobes  usually  ser¬ 

rate.  (Coccineae).  44. 

13.  Leaves  yellow-green  often  slightly  pubescent;  fruit  soft 

at  maturity.  (Tenuifoliae).  34. 

13.  Leaves  blue-green,  usually  glabrous;  fruit  hard  at  ma¬ 

turity.  (Pruinosae).  38. 

—  Crus-galli.  — 

14.  Leaves  not  lobed.  15. 

14.  Leaves  somewhat  lobed.  16. 

15.  Leaves  f-4  in.  long.  C.  crus-galli. 

15.  Leaves  J-2§  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.  suborbieulata. 

—  Macracanthae. — 

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  %  in.  thick  or  less;  leaves  large.  C.  succulenta. 

22.  Fruit  J  in.  thick  or  less;  leaves  small.  C.  neoflv/vialis. 


Tkees  of  the  Northern  United  States 


65 


—  Brainerdianae. — 

23.  Fruit  and  corymbs  pubescent ;  calvx-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.  oraincrdi. 

—  Botnndifoliae. — 

24.  Leaves  longer  than  wide.  25. 

24.  Leaves  about  as  wide  as  long.  26. 

25.  Leaf  lobes  acuminate.  C.  lawrentiana. 

25.  Leaf  lobes  acute.  C.  lucorum. 

26.  Leaf-lobes  acuminate.  C.  irrasa. 

26.  Leaf -lobes  acute  or  obtuse.  27. 

27.  Calyx-tube  prominent;  fruit  subglobose.  C.  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.  chrysocarpa. 

— -  Virides. — 

29.  Leaves  ovate;  lobes  shallow;  fruit  yellow-red.  C.  ovata. 

29.  Leaves  oblong-ovate,  lobes  deep;  fruit  bright  red,  glau¬ 

cous.  C.  viridis , 

—  Intricatae. — •  * 

30.  Foliage  and  fruit  pubescent;  corymbs  villous.  31. 

30.  Foliage,  fruit,  and  corymbs  glabrous.  •  32. 

31.  Fruit  globose,  greenish  to  reddish-brown.  C.  intricata. 

31.  Fruit  ellipsoid  or  pyriform,  yellow.  C.  stonei. 

32.  Leaves  cordate,  lobed.  C.  popuUfolia. 

32.  Leaves  euneate,  lobed.  33. 

33.  Leaves  elliptic-ovate ;  fruit  pyriform-ellipsoid.  C.  stra- 

minea. 

33.  Leaves  ovate  to  oval ;  fruit  globose  or  subglobose,  red¬ 

dish-green  to  reddish-brown.  C.  boyntoni, 

—  Tenuifoliae. — 

34.  Fruit  ellipsoid,  ovoid,  or  pyriform;  calyx-lobes  entire.  35. 

34.  Fruit  compressed-globose  or  subglobose.  36. 

35.  Leaves  much  lobed;  fruit  small,  %-%  in.  thick,  with 

rather  firm  flesh.  C.  roanensix. 


66 


Field  Manual 


35.  Leaves  not  conspicuously  lobed;  fruit  large,  in.  thick, 

with  soft  flesh.  C.  macrosperma. 

36.  Lobes  of  the  leaves  reflexed.  C.  g.rayana. 

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.  leiopliylla. 

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. 

43.  Leaves  ovate.  C.  pruinosa. 

—  Coocineae.  — 

44.  Mature  leaves  usually  glabrous  above;  young  foliage 

bronze-green.  45. 

44.  Mature  leaves  tomentose  above;  young  foliage  yellow- 

green.  50. 

45.  Leaves  oblong-ovate.  46. 

45.  Leaves  broadly  ovate.  47. 

46.  Corymbs  nearly  glabrous.  C.  villipes. 

46.  Corymbs  very  pubescent.  C.  anomala. 

47.  Corymbs  and  fruit  glabrous.  C.  coccinioides. 

47.  Corymbs  and  fruit  pubescent  or  tomentose.  48. 

48.  Leaves  on  the  vegetative  shoots  cuneate.  49. 

48.  Leaves  on  the  vegetative  shoots  cordate.  C.  albicans. 

49.  Leaves  concave,  11-3  in.  long,  ll-2f  in.  wide.  C.  pringlei. 

49.  Leaves  plane,  1-1-4  in.  long,  11-3J  in.  wide.  C.  coooinea. 

50.  Leaves  on  the  vegetative  shoots  cuneate  at  the  base.  51. 

50.  Leaves  on  the  vegetative  shoots  cordate.  C.  mollis. 

51.  Lobes  of  the  leaves  broad,  shallow,  acuminate.  C.  ar 

noldiana. 


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.  monogyna. 

— -  Parvifoliae.  — 

53.  Leaves  small,  subcoriaceous,  corymbs  1-3-flowered.  C. 

uniflora. 

—  Douglasianae.  — 

54.  Leaves  subcoriaceous,  petioles  J-f  in.  long.  C.  douglasii. 

—  Cordatae.  — 

55.  Leaves  often  conspicuously  3-5-lobed,  petioles  $-2  in. 

long.  C.  vhaenopyrum. 

1.  Crataegus  crus-galli  L.  Cockspur  Hawthorn.  A  small 
tree  with  spreading  branches  and  numerous  slender  thorns. 
Leaves  coriaceous,  shining  above,  sharply  serrate.  Fruit 
ellipsoid-ovoid  to  subglobose,  grenish  to  red,  flesh  hard,  re¬ 
maining  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  Haw¬ 
thorn.  A  small  tree  with  spreading  branches  and  a  broad 
crown,  with  few  thorns.  Leaves  oblong-cuneiform,  spatulate, 
or  obovate,  rough-pubescent  above,  white-pubescent  or  tomen- 
tose  beneath.  Fruit  subglobose  to  short-ellipsoid,  yellow, 
orange,  or  red.  Ky.  to  Mo.  and  the  Gulf  States. 

3.  Crataegus  schizophylla  Eggl.  Martha’s  Vineyard  Haw¬ 
thorn.  A  small  tree  with  irregular  ascending  branches  and 
numerous  thorns.  Leaves  oblong-ovate  to  ovate,  coarsely  ser¬ 
rate  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.  Leaves 


Fiei.d  Manuai, 


6S 

oblong-obovate  to  oval.  Fruit  short-ellipsoid  to  subglobose, 
orange-red,  slightly  pubescent.  Rich  bottom  lands.  Ill.  and 
Mo. 

6.  Crataegus  cuneiformis  (Marsh.)  Eggl.  Marshall’s  Haw¬ 
thorn.  A  small  tree  with  widely  spreading  branches,  dark 
brown  scaly  bark,  and  numerous,  often  branched  thorns. 
Leaves  oblanceolate-obovate.  Fruit  ellipsoid-pyriform,  scarlet 
or  dark  red.  N.  Y.  and  Pa.  to  Ya.  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  Hawthorn. 
A  shrub  or  small  tree  with  ascending  branches  forming  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  Ya. 

9.  Crataegus  suborbiculata  Sarg.  Caughuawaga  Haw¬ 
thorn.  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 
limestone  areas.  Montreal  to  Mich. 

10.  Crataegus  succulenta  Schrad.  Longthorn  Hawthorn. 
A  small  tree  with  ascending  branches  forming  a  broad  irregu¬ 
lar  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  Hawthorn. 
A  small  tree  with  ascending  and  spreading  branches,  and 
numerous  thorns.  Leaves  elliptic-ovate  to  obovate,  doubly  ser¬ 
rate  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  Haw¬ 
thorn.  A  shrub  or  small  tree  with  ascending  and  spreading 
branches  forming  a  broad  crown,  with  stout  thorns  and  tomen- 
tose  twigs.  Leaves  rhombic-ovate,  acute  or  acuminate  at  the 


Trees  of  the  Northern  United  States 


69 


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  flattened 
crown  and  with  numerous  curved  thorns.  Leaves  oblong  to 
obovate,  finely  doubly  serrate  or  lobed.  Fruit  globular  or 
nearly  so,  clierry-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,  cherrv-red  to  scarlet.  N.  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  douDiy  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  pyriform — 
ellipsoid,  crimson.  111.  and  Wis. 

17.  Crataegus  irrasa  Sarg.  Blanchard’s  Hawthorn.  A 

shrub  or  small  tree  with  numerous  spines.  Leaves  ovate  to 
elliptic,  doubly  serrate  or  lobed.  Fruit  subglobose  to  short- 
ellipsoid,  red  or  scarlet,  somewhat  pubescent.  Quebec  to  Vt. 
and  N.  Y. 

18.  Crataegus  macauleyae  Sarg.  Macauley’s  Hawthorn. 

A  small  round-topped  tree  with  somewhat  pendulous  branches. 
Leaves  ovate  to  oval,  doubly  serrate  or  lobed.  Fruit  sub- 
globose  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  Hawthorn. 

A  beautiful,  round-topped  shrub  or  small  tree  with  numerous 
thorns.  Loaves  ovate-orbicular  or  obovate,  doubly  serrate 

or  lobed,  shining  above.  Fruit  depressed-globose  to  short- 
ovoid,  red.  N.  S.  and  N.  B.  to  Saskatch.,  south  to  N.  C., 
Neb.,  and  N.  M. 


70 


Field  Manual 


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. 
Ivy.  and  Mo. 

22.  Crataegus  vlridis  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.  Allu¬ 
vial  soil.  Va.  to  Fla.,  Ind.,  Ill.,  Kan.,  and  Texas. 

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  of  becoming  dark  reddish-brown,  somewhat  pubescent. 
Open  rocky  woods.  N.  Eng.  and  N.  Y.,  south  to  S.  Car. 
and  Mo. 

24.  Crataegus  stonei  Sarg.  Stone's  Hawthorn.  A  much- 
branched  shrub  or  small  tree  with  prominent  thorns.  Leaves 
oblong  to  oblong-ovate,  doubly  serrate  or  lobed.  Fruit  pyri¬ 
form  to  short-ellipsoid,  light  yellow  or  yellow-green  tinged 
with  red.  Rocky  soil.  Mass.,  Conn.,  and  N.  Y. 

25.  Crataegus  populifolia  Walt.  Poplar-leaf  Hawthorn. 
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  aeute  lobes.  Fruit  globose, 
light  red,  without  angles.  Ya.  to  S.  C. 

26.  Crataegus  straminea  Beadle.  Alleghany  Hawthorn. 
An  irregularly  branched  shrub  or  small  tree  with  occasional 
thorns.  Leaves  elliptic-ovate,  doubly  serate  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  Hawthorn.  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 


71 


28.  Crataegus  roanensis  Ashe.  Roan  Mountain  Hawthorn. 
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  Wis.,  N.  C.,  and  Tenn. 

29.  Crataegus  macrosperma  Ashe.  Variable  Hawthorn. 
A  shrub  or  small  tree  with  ascending  branches  and  numerous 
thorns.  '  Leaves  elliptic-ovate  to  broadly  ovate,  doubly  ser¬ 
rate  and  somewhat  lobed.  Fruit  ellipsoid  or  pyriform,  scarlet 
to  crimson,  often  glaucous.  N.  S.  and  Me.  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  sub- 
globose  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  subglobose, 
slightly  angular,  dark  cherry-red.  N.  Eng.  to  Mich,  and  Pa. 

32.  Crataegus  populnea  Ashe.  Gruber’s  Hawthorn.  A 
shrub  or  small  tree  with  flattened  round  crown.  Leaves  broadly 
ovate  to  elliptic-ovate,  slightly  villous,  serrate  or  doubly  ser¬ 
rate,  sometimes  lobed.  Fruit  glabrous,  short-ellipsoid  scar¬ 
let.  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  wdth  4  to  5  pairs  of  acute 
lobes.  Fruit  short-ellipsoid  to  pyriform,  slightly  angled,  dark 
red.  Vt.  to  Wis.  south  to  Pa. 

34.  Crataegus  rugosa  Ashe.  Rugose  Hawthorn.  A  shrub 
or  small  tree  with  ascending  "branches.  Leaves  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  fllipes  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  Hawthorn.  A 
shrub  or  small  tree  with  ascending  branches  forming  an  ir¬ 
regular  crown,  and  with  numerous  thorns.  Leaves  narrowly 
ovate  to  deltoid,  serrate  or  doubly  serrate,  lobed  toward  the 
apex,  glabrous,  dark  green  above.  Fruit  globose,  angular, 
red.  Pa.  to  Ind.,  south  to  W.  Ya.  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  villipes  Ashe.  Thinleaf  Hawthorn.  A  tree 
with  strongly  ascending  branches.  Leaves  elliptic-ovate,  ser¬ 
rate  or  doubly  serrate  with  4-6  pairs  of  acute  or  acuminate 
lobes,  pubescent  or  scabrous.  Fruit  pyriform  or  ellipsoid,  crim¬ 
son.  Maine  to  Quebec  to  Mich.,  south  in  the  mountains 
to  N.  C. 

41.  Crataegus  anomala  Sarg.  Oblong-leaf  Hawthorn.  A 
shrubby  tree  with  numerous  thorns.  Leaves  oblong  to  ovate, 
serrate  or  doubly  serrate  with  acute  lobes.  Fruit  pyriform- 
ellipsoid,  crimson.  Quebec  to  Mass,  and  N.  Y. 

42.  Crataegus  coccinioides  Ashe.  Eggert’s  Hawthorne.  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 


Thicks  ok  'i'li  io  North  win  I/nitko  Htatich 


73 

pyri  form,  pubescent,  red.  Western  N.  Fn g.  Io  III.,  Houtli  to  Pa. 

44.  Crataegus  coccinea  L.  Sour  let  Hawthorn.  A  himu.I1 
tree  with  ascending  arid  spreading  hranelicH  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  cunsiderahle  decorative  value.  Conn, 
to  Out.,  111.,  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  sub- 
globose  or  somewhat  pyriform,  dark  red.  Western  N.  Mug. 
to  Mich.,  south  to  Del.  and  Term. 

4(i.  Crataegus  arnoldiana  Sarg.  Arnold’s  Hawthorn.  A 

small  tree  with  ascending  branches,  forming  a  broad  crown, 
and  numerous  long  thorns.  Leaves  broadly  ovate  to  oval,  ser¬ 
rate  or  doubly  serrate  with  broad  shallow  lobes,  tomentose  or 
scabrous  above.  Fruit  globose  or  subglobose,  bright  crimson, 
slightly  pubescent;  flesh  thick,  juicy,  and  edible.  Muss,  and 
Conn. 

47.  Crataegus  submbllis  Sarg.  Emerson's  Hawthorn.  A 

small  tree  with  spreading  branches,  forming  a  broad  symmet¬ 
rical  crown,  and  with  numerous  thorns.  Leaves  ovate,  doubly 
serrate  find  acutely  lobed,  tomentose,  becoming  scabrate.  Fruit 
short  ellipsoid  to  pyriform,  orange-red,  slightly  tomentose, 
edible.  '  Quebec  to  Mass,  and  N.  V. 

4x.  Crataegus  mollis  &  <>.)  Seheele.  Downy  I  law 
thorn.  A  tree  with  spreading  branches  and  densely  pubescent 
twigs,  forming  a  broad-topped  crown.  Leaves  broadly  ovate, 
doubly  serrate  with  narrow  acute  lobes,  densely  tomentose. 
Fruit  short-ellipsoid  to  subglobose,  scarlet,  edible.  Out.  to 
S.  Dak.,  Term.,  and  Ark. 

49.  Crataegus  monogyna  .(aeip  Fuglish  Hawthorn.  A 
shrub  or  tree  with  ascending  branches  and  numerous  thorns. 
Leaves  ovate,  sharply  5  15  lobed  or  cleft,  dark  green  and  glab¬ 
rous  above  when  mature.  Fruit  globose  or  subglobose,  red. 
Native  of  Europe.  Sparingly  escaped  in  the  eastern  states. 

50.  Crataegus  uniflbra  Mueneh.  Dwarf  Hawthorn.  An 
irregular  shrub  or  small  tree  with  numerous,  slender,  straight, 


74 


Field  Manual 


thorns.  Leaves  obovate  to  spatulate,  crenate  or  crenate-ser- 
rate,  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 
shrftb  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.  Washington 
Hawthorn.  A  shrub  or  small  tree  with  strongly  ascending 
branches  and  numerous  thorns.  Leaves  ovate-triangular,  simply 
or  doubly  serrate,  often  3-5  lobed,  bright  green  and  glabrous 
above.  Fruit  depressed-globose,  scarlet.  Moist  rich  ground. 
A  very  desirable  species  for  cultivation.  Va.  to  Ga.,  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  pentamer- 
ous;  carpel  1,  hypanthium  deciduous;  drupe  mostly  edible. 

1.  Terminal  bud  usually  present;  leaves  eonduplicate  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  ^  in.  long;  leaves  ovate,  ab¬ 

ruptly  acute  at  the  apex;  flowers  corymbose,  terminat¬ 
ing  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.  3. 

3.  Flowers  in  umbellate  or  corymbose  clusters.  4. 

3.  Flowers  in  racemes.  6. 


Trees  of  the  Northern  United  States 


75 


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. 

5.  Leaves  ovate-lanceolate  to  lanceolte;  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. 

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

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

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

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

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

long  as  the  blade.  '  8. 

7.  Leaves  abruptly  long-acute  or  acuminate,  ovate  to  round- 
ovate  ;  petiole  J  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.  9. 

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

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

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

ers  white.  P.  americana. 

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

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

10.  Leaves  pubescent  beneath,  not  pointed  or  only  slightly 

so,  ovate  or  obovate.  P.  domestica. 

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

P.  angustifoMa. 

11.  Leaves  ovate,  drupe  dark  purple,  with  a  bloom.  P.  alle- 
ghan.ien.ns. 


70 


Field  Manual 


Cherries. 

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

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.,  Texas, 
Colo.,  and  Ohio. 

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

4.  Prunus  Pennsylvania  L.  f.  Red  Cherry.  A  small 
tree  with  sour  globose,  red  drupes.  Leaves  oval  or  lanceo¬ 
late,  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-ac"- 
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,  rounded 


Trees  of  the  Northern  United  States 


77 


at  the  base,  very  resinous  when  young.  Self-prunes  the  fruit¬ 
ing  branchlets.  Native  of  Europe.  N.  H.  and  Mass,  to 
N.  Y.  and  Ohio. 

Plums  and  Apricot. 

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

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

11.  Prunus  angustifolia  Marsh.  Chickasaw  Plum.  A 
small  tree  with  thorn-like  stunted  branches.  Loaves  acute, 
serrulate,  often  rounded  at  the  base.  Drupe  globose,  red,  and 
edible.  In  dry  soil.  N.  .1.  to  Fla.,  west  to  Rocky  Mts. 

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

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

28.  Amygdalus  L.  Peach. 

Trees  or  shrubs  with  alternate,  simple,  serrate,  pinnately- 
veined  leaves  with  2-4  disk-like  glands  at  the  edge  of  the 


Field  Manual 


78 

base  of  the  blade,  with  terminal  bud,  stipular  sears  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. 

Fabadeae.  Pea  Family. 

4  Cassiatae.  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  hat  bean. 

1.  Cercis  canadensis  L.  Redbud.  A  small  tree  with 
bright  red-purple  flowers  before  the  leaves;  fine  for  orna¬ 
mental  purposes.  Wood  hard  and  heavy,  beautifully  varie¬ 
gated.  In  rich  soil.  Easily  cultivated.  Ont.  and  N.  Y.  to 
Iowa,  Neb.,  N.  J.,  Fla.,  and  Texas. 

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.  triacanthos. 

1.  Pod  obliquely  oval,  1-seeded,  not  pulpy;  leaflets  thicker, 
darker  green,  usually  larger,  ovate-lanceolate  or  lan¬ 
ceolate,  the  margin  more  crenulate.  G.  aquatica. 

1.  Gleditsia  triacanthos  L.  Honey-locust.  A  large  tree 
of  rapid  growth,  usually  with  stout  branching  or  simple  thorns 
and  with  rough  bark,  the  catkin-like  racemes  often  appearing 


Trees  op  the  Northern  United  States 


79 


on  the  main  trunk  and  larger  branches.  Used  as  a  hedge 
plant.  Autumn  leaves  pure  yellow.  Wood  heavy,  hard,  strong 
and  tough;  used  for  fencing,  fuel  and  wagon  hubs.  Sprouts 
freely  from  the  roots  if  disturbed  by  plowing.  Grows  well 
in  dry  or  sandy  soil.  Ont.  and  N.  Y.  to  S.  Dak.,  Ga.,  Kan., 
and  Texas. 

2.  Gleditsia  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  super¬ 
posed  axillary  buds,  and  large  cholocate-colored  pith. 

Flowers  greenish,  diecious,  both  types  with  vestiges  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,  of  coarse 
texture,  and  taking  a  good  polish;  used  to  some  extent  in 
cabinet-work.  In  rich  soil.  Ont.  to  Ohio  and  Penn.,  Tenn., 
S.  Dak.,  and  Okla. 


Fdbatae.  Pea  Subfamily. 

32.  Cladrastis  Raf.  Yellow-wood. 

* 

Trees  with  alternate,  odd-pinnate  leaves  with  entire  leaf¬ 
lets,  with  the  petiole  base  cavering  the  superposd  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.  Tn  rich  soil;  much  planted.  Ky.,  Mo.,  Tenn., 
and  N.  Oar. 


PiBJiD  Manual 


«u 


33.  Robinia  L.  Locust. 

Trees  or  shrubs  with  alternate  add-pinnate  non-punctate 
loaves  and  with  stipular  spines. 

Flowers  showy,  in  racemes;  fruit  a  flat  bean. 

1.  Twigs,  petioles  and  pods  glabrous  or  nearly  so;  (lowers 
white.  It.  pxeudoacacia. 

1.  Twigs  and  petioles  glandular;  pods  hispid;  flowers 
pinkish.  It.  viscom. 

1.  Robinia  pseudoacacia  L.  Common  Locust.  A  large 
slender  tree  with  very  rough  bark,  of  rapid  growth.  Wood 
very  heavy,  hard,  strong,  tough,  valuable,  and  very  durable  in 
contact  with  the  ground;  used  for  posts,  railroad  ties,  wagon 
hubs,  furniture,  and  in  ship  building.  All  parts  of  the  plant 
very  poisonous.  It,  is  troublesome  from  sprouting  from  the 
roots.  Penn,  and  Ohio  to  (la.,  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  (la.  Also 
escaped  in  Middle  and  Eastern  States. 


Order,  Celastrai.KS. 

Ithamnaoeae.  Buckthorn  Fa mily. 

34.  Rhamnus  (Tourri.)  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  dieeious  or  imperfectly  mono- 
sporangiato,  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  pedtinelod;  flowers  bisporangiate. 
It.  caroliniana. 

1.  Leaves  with  3  or  4  pairs  of  lateral  veins,  the  basal  pair 
prominent;  nutlets  of  the  fruit  grooved;  flowers 
dieeious  or  imperfectly  monosporangiato.  It.  pa- 
thartica. 


Thicks  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  Ivan.,  Fla.,  and  Texas. 

2.  Rhamnus  cathartica  L.  Common  Buckthorn.  A 
shrub  or  small  tree  with  black  injurious  fruit.  Somewhat 
thorny  and  used  for  hedges.  The  fruit  yields  a  dye  and  has 
powerful  medicinal  properties.  Introduced  from  Europe. 
Eastern  states. 


Celastracene.  Stafftree  Family. 

35.  Euonymus  (Tourn.)  L.  Walioo. 

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  cap¬ 
sule;  seeds  enclosed  in  a  red  aril. 

1.  Flowers  purple;  cymes  6-15  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 . 

europaeus. 

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  points.  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. 

llioaceae.  Holly  Family. 

t 

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;  and  with  berry-like  drupes  con¬ 
taining  several  small  stones. 

Flowers  small,  in  axillary  clusters  or  solitary,  mostly  im¬ 
perfectly  dieeious. 


82 


Field  Manual 


1.  Leaves  thick,  persistent,  evergreen,  shiny.  I.  opaoa. 

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,  nut¬ 
lets  ribbed.  I.  montana. 

1.  Ilex  decidua  Walt.  Deciduous  Holly.  A  shrub  or 

small  tree  with  liglit-gray,  glabrous  twigs  and  red  drupes. 

ood  hard  and  white.  In  swamps  and  low  ground.  D.  C. 

to  Fla.,  Kan.,  and  Texas. 

2.  Ilex  montana  (T.  &  G.)  Gr.  Mountain  Holly.  A 

shrub  or  slender,  erect  tree  growing  in  mountain  woods. 
Drupes  red.  N.  Y.  to  Ga.,  and  Ala. 

3.  Ilex  opaca  Ait.  American  Holly.  A  trfee  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,  ana  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  Texas. 


Staphyleaceae.  Bladdernut  Family. 

37.  Staphylea  L.  Bladdernut. 

Shurbs  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.  Branching 
a  sympodial  dichotomy.  In  moist  soil.  Quebec  to  Minn.,  S. 
Car.,  and  Kan. 


Trees  of  the  Northern  United  States 


s:( 


Order,  Sapindales. 

Sapindaoeae.  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  TI.  &  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  numer¬ 
ous  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  spontaneous 
from  seed  in  Indiana. 

Aesculaoeae.  Buckeye  Family. 

40.  Aesculus  L.  Buckeye,  Horse-chestnut. 

Trees  or  shrubs  with  opposite  palmately  compound  leave^. 

Flowers  imperfectly  monosporangiate,  zygomorphie,  in  ter¬ 
minal  panicles,  capsules  leathery,  containing  large  shining  nut¬ 
like  seeds. 

1.  Flowers  white,  mottled  with  yellow  and  purple;  leaf¬ 
lets  abruptly  acuminate;  winter  buds  gummy;  cap¬ 
sule  spiny  ;  bundle  scars  arranged  in  a  curved  line. 
A.  hippo  castanum. 

1.  Flowers  yellow  or  purplish;  leaflets  acuminate,  more  or 
less  abrupt;  winter  buds  not  gummy;  bundle  scars 
arranged  in  3  areas.  2. 


&4 


Field  Manual 


2.  Capsule  spiny,  stamens  exserted.  3. 

2.  Capsule  glabrous ;  stamens  not  longer  than  the  petals, 

corolla  yellow  or  purplish.  A.  oetandra. 

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.  Es¬ 
caped  from  cultivation;  native  of  Asia. 

2.  Aesculus  glabra  Willd.  Ohio  Buckeye.  A  large  tree 
with  rough  and  fetid  bar,,.  Leaves,  young  shoots,  and  seeds 
poisonous  to  cattle.  Wood  light  and  hard  to  split;  used  for 
making  artificial  limbs,  wooden-ware,  and  paper  pulp.  Penn, 
to  Ala.,  Mich.,  Neb.,  and  Okla. 

3.  Aesculus  arguta  Buckl.  Western  Buckeye.  A  shrub¬ 
like  small  tree  with  smooth  bark.  On  flood  plains.  Mo. 
and  Kan.  to  Texas.  Reported  from  Iowa. 

4.  Aesculus  oetandra  Marsh.  Yellow  Buckeye.  A  large 
tree  witli  brown-  scaly  bark.  Seeds  poisonous.  Wood  light 
and  hard  to  split;  used  for  making  artificial  limbs,  wooden- 
ware  and  paper  pulp.  Aesculus  oetandra  hybridia  (DC.) 
Sarg.  has  purplish  or  pink  flowers,  leaflets  pubescent  beneath, 
and  light  brown  bark.  Penn,  to  Ga.,  Iowa  and  Texas. 

Aceraceae.  Maple  Family. 

41.  Acer  (Tourn.)  L.  Maple. 

Trees  or  shrubs  with  opposite  leaves,  with  3-5  bundle  scars 
in  the  harrow,  contiguous  leaf  scars,  and  with  a  terminal  bud 
showing  several  pairs  of  visible  scales. 

Sap  watery  or  sometimes  milky,  often  saccharine;  fruit  a 
2-winged  samara.  Usually  diecious  or  imperfectly  diecious. 

1.  Leaves  pinnate  or  trifoliate;  twigs  green,  glaucous.  A. 
negnndo. 

1.  Leaves  simple.  2. 


Trees  oe  the  Northern  United  States 


85 


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  t'oii- 

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. 
saccharu m. 

5.  Leaves  very  sharply  and  finely  serrate,  3-lobed  at  the 

outer  end,  widest  above  the  middle,  the  lobes  ab¬ 
ruptly  narrow-acuminate,  brown  pubescent  below 
when  young;  twigs  green,  striped  with  darker  lines; 
flowers  racerned,  terminal,  unfolding  after  the  leaves. 
A.  pennsy Ivanieum . 

5.  Leaves  dentate-serrate  or  lobed,  not  abruptly  narrow- 

acuminate  ;  twigs  not  striped.  6. 

6.  Leaves  broadly  3-5-lobed,  the  lobes  rather  regularly  and 

continuously  dentate-serrate  or  dentate-crenate ;  flow¬ 
ers  racemed,  terminal,  unfolding  after  the  leaves.  7. 

6.  Leaves  usually  with  3-7  slender,  long  and  pointed  lobes, 
the  lobes  irregularly  or  interruptedly  serrate  or  ser¬ 
rate-dentate;  flowers  in  dense  sessile,  lateral  clusters, 
appearing  before  the  leaves.  8. 


86 


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  or  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  5-lobed,  lobes  slender,  aeute, 

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  pres¬ 
ent.  A.  rubrum. 

1.  Acer  platanoicles  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  fine  tree 
with  spreading  branches.  Leaves  deeply  3-5  lobed.  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  be¬ 
neath,  at  least  when  young.  In  damp  rocky  woods.  Newf.  to 
Man.,  south  to  N.  Car.,  Tenn.,  Minn.,  and  Iowa. 


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  cor¬ 
date  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  Texas. 

6.  Acer  nigrum  Mx.  Black  Maple.  A  large  fine  tree 

with  rough  blackish  bark.  Leaves  cordate  or  truncate  at  tjie 

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.  Out. 
and  Yt.  to  Ga.,  S.  Dak.,  La.,  and  Ark. 

7.  Acer  rubrum  L.  Bed  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  consideraDle 
value  when  it  shows  a  “curly  grain.”  Leaves  crimsone,  scarlet 
or  yellow  in  the  autumn.  Self-pruning  like  the  following.  In 
swamps  and  low  ground,  also  on  moist  hillsides.  N.  S.  to 
Man.,  Pla.,  Neb.,  and  Texas. 

8.  Acer  saccharinum  L.  Silver  Maple.  A  large  tree 
with  flaky  bark,  the  twigs  often  reddish,  self-pruned  by  basal 
joints.  Leaves  deeply  5-lobed,  the  lobes  rather  narrow,  acumi¬ 
nate,  coarsely  and  irregularly  dentate,  truncate  or  slightly 
cordate  at  the  base,  green  above,  silvery  white  and  more  or 
less  pubescent  beneath.  A  fine  shade  tree  and  much  planted. 
Wood  soft  and  w'hite ;  used  i  for  furniture.  Yields  a  small 
amount  of  sugar.  Along  streams.  N.  B.  to  Pla.,  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 


88 


.Field  Manual 


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;  sta¬ 
mens  five,  styles  three;  drupe  red. 

1.  Petioles  not  completely  covering  the  axillary  buds; 
leaflets  entire;  rackis  of  the  leaf  wing-margined; 
leaflets  7-31;  twigs  and  the  red  drupes  pubescent. 
B.  copallina. 

1.  Petioles  covering  the  axillary  buds;  leaflets  serrate.  2. 

2.  Leaves  and  twigs  velvety-pubescent.  B.  hirta. 

2.  Leaves  and  twigs  glabrous,  somewhat  glaucous.  B. 
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.  Tn  dry 
soil.  Me.  and  Out.  to  Fla.,  Minn.,  Neb.,  and  Texas. 

2.  Rhus  hirta  (L.)  Sudw.  Staghorn  Sumac.  A  small 
tree  or  shrub  with  red,  pubescent  drupes.  Wood  very  soft 
and  brittle.  In  dry  or  rocky  soil.  A  good  lemonade  or 
“sumacade”  is  made  by  steeping  the  drupes  and  sweetening 
to  taste.  Leaves  used  for  tanning.  Wood  soft,  greenish- 
yellow.  N.  S.  to  Ga.,  Ont„  S.  Dak.,  Mo.,  and  Iowa. 

3.  Rhus  glabra  L.  Smooth  Sumac.  A  shrub  or  small 
tree  with  dense  panicles  of  small  crimson  drupes  covered  with 
short  acid  hairs.  Noted  for  its  beautiful,  brilliant,  red-colored 
leaves  in  autumn.  Leaves  used  for  tanning.  Common  on  hill¬ 
sides  and  bluffs.  N.  S.  to  Minn.,  Fla.,  Miss.,  and  La. 


Trees  of  the  Northern  United  States 


89 


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  bisporan- 
giate  ;  drupes  gray  or  white. 

1.  Toxicodendron  vernix  (L.)  Ktz.  Poison  Sumac.  A 
shrub  or  small  tree,  very  poisonous  to  the  touch.  Drupes 
gray,  glabrous  in  loose  axillary  panicles.  In  swamps  and  wet 
places.  Wood  soft,  yellowish  brown,  poisonous.  Maine  to 
Fla.,  Ont.,  Minn.,  Mo.,  and  La. 

44.  Cotinus  Adans.  Smoketree. 

Small  trees  or  shrubs  with  alternate,  simple  pinnately 
veined,  entire,  deciduous  leaves  and  fragrant  resinous  sap. 

Flowers  small,  imperfectly  bisporangiate,  on  a  large  ter¬ 
minal  panicle;  stamens  5,  styles  3,  lateral;  drupe  oblique, 
small,  compressed;  buds  clustered  at  the  tip  of  the  twig. 

1.  Blade  of  the  leaf  slightly  decurrent  on  the  petiole, 

thin,  glabrous  or  slightly  pubescent  beneath.  C. 
americanus. 

1  Leaves  mostly  rounded  or  obtuse  at  the  base,  coii- 

aceous,  more  pubescent.  C.  cotinus. 

1  Cotinus  americanus  Nutt.  American  Smoketree.  A 

small  wide-branched  tree.  Wood  soft,  orange-yellow,  yielding 
a  rich  dve.  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. 

Hamamelidaceae)  Witch-hazel  Family. 

Subfamily,  Hamamelidatae. 

45.  Hamamelis  L.  Witch-hazel. 

Shrubs  or  small  trees  with  2-ranked,  simple,  inequilateral, 
straight -veined  leaves  and  stalked  axillary  buds. 

Flowers  bisporangiate  or  imperfectly  bisporangiate,  in 
axillary  clusters;  fruit  a  bilocular,  woody  or  cartilaginous, 
nut-like  capsule. 


90 


.Field  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  banks. 
N.  B.  and  N.  S.  to  Minn.,  Mo.,  Fla.  and  Texas. 

Subfamily,  Attingiatae. 

46.  Liquidambar  L.  Sweet-gum. 

Frees  with  alternate,  simple,  palmately  veined,  fragrant, 
star-shaped,  serrate  leaves  and  5-angled  pith. 

Sap  resinous,  aromatic;  flowers  monecious,  in  heads,  the 
staininate  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  covered 
with  corky  ridges.  Leaves  with  a  peculiar  sweet  fragrance 
when  crushed.  Autumn  leaves  red,  yellow,  and  brown.  Wood 
valuable,  of  medium  weight,  hard,  not  strong,  tough,  and  of 
fine  texture,  reddish  brown,  difficult  to  season.  Sometimes 
used  as  a  substitute  for  black  walnut.  Used  for  furniture, 
veneer,  wooden  plates,  plaques,  baskets,  hat  blocks  and  wagon 
hubs.  In  low  ground.  Conn.,  N.  Y.  and  Ohio  to  Fla.,  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. 
oocidentalis. 

1.  Bark  exfoliating  in  large  plates;  leaves  somewhat  5- 
lobed,  in  some  varieties  deeply  lobed.  P.  orientalis. 

1  •  Platanus  occidentalis  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;  the  largest 


Trees  op  the  Northern  United  States 


91 


trunks  usually  hollow,  sometimes  as  much  as  42  feet  m  cir¬ 
cumference.  Autumn  leaves  brown.  Wood  rather  hard,  com¬ 
pact,  coarse-grained,  difficult  to  split,  tough,  and  of  a  light- 
brown  color;  used  for  tobacco  boxes,  cooperage,  cabinet-work, 
and  finishing  lumber.  Along  the  banks  of  streams  and  in 
moist  ground,  but  grows  well  in  ordinary  mesophytic  condi¬ 
tions.  Me.  to  Ont.  and  Minn.,  Fla.,  Kan.,  and  Texas. 

2.  Platanus  oriental is  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,  Urticales. 

Ulmaceae.  Elm  Family. 

48.  Ulmus  (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  clus¬ 
ters  or  racemes;  fruit  a  samara;  trees  of  rapid  growth. 

1.  Leaves  very  rough  above;  twigs  not  corky-winged  and 
not  self-pruned,  but  large  numbers  of  lateral  buds 
cut  off;  inner  bark  sometimes  mucilagious.  2. 

1.  Leaves  smooth  or  sometimes  somewhat  rough  above.  3. 

2.  Inner  bark  very  mucilaginous,  buds  rusty-downy,  sa¬ 

mara  much  less  than  1  in.  long.  U.  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.  amerieana. 

3  None  of  the  branches  with  corky  ridges;  twigs  glab¬ 
rous  or  nearly  so,  not  self-pruned;  samara  glabrous 
or  nearly  so,’  deeply  notched.  U.  campestris. 

3.  Some  or  all  of  the  branches  corky-winged,  or  twigs 
puberulent,  seif -pruned;  samara-faces  pubescent.  4. 


92 


Field  Manual 


4.  Most  of  the  branches  with  corky  wing-like  ridges; 
twigs  glabrous  or  nearly  so;  leaves  .1-3  in.  long. 
U.  alata. 

4.  Branches  often  with  corky  wing-like  ridges;  twigs 
puberulent;  leaves  2-5  in.  long.  U.  thomasi. 

1.  Ulmus  americana  L.  White  Elm.  A  large  tree  of 
rapid  growth,  with  the  bark  in  thick,  rough  ridges;  much 
cultivated  in  cities  and  along  roadsides.  Trunks  up  to  33 
feet  in  circumference.  Samara  ovate-oval,  its  faces  glabrous. 
Wood  heavy,  hard,  flexible,  and  very  tough;  used  for  wheel- 
hubs,  saddle-trees,  rough  cooperage  and  furniture,  in  boat  and 
ship  building,  in  the  construction  of  cars  and  wagons,  and 
especially  for  barrel  hoops.  Common  on  bluffs  and  on  the 
flood  plains  of  rivers  and  creeks.  Graceful  in  form  and  very 
suitable  for  cultivation.  Newf.  to  Man.,  Fla.,  and  Texas. 

2.  Ulmus  thomasi  Sarg.  Cork  Elm.  A  large  tree  with 
puberulent  young  twigs,  the  branches  or  some  of  them  with 
corky  wings.  Samara  oval,  its  margins  densely  ciliate.  Wood 
harder,  stronger,  and  more  durable  than  that  of  the  White 


Elm. 

Mo. 

In  rich 

soil. 

Quebec  to  Out., 

,  Minn.,  Ky.,  Neb., 

and 

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.,  Ill.,  Mo.,  and  Texas. 

4.  Ulmus  campestris  L.  English  Elm.  A  tree,  rather 
pyramidal  in  shape,  the  twigs  ascending,  not  drooping  except 
in  “weeping”  forms.  Samara  not  ciliate,  nearly  or  quite 
glabrous.  A  good  timber  tree.  Cultivated,  from  Europe. 

5.  Ulmus  fulva  Mx.  Slippery  Elm.  A  medium-sized  tree 
with  rough  grayish-brown  fragrant  bark  and  rough-pubescent 
twigs.  Samara  oval-orbicular,  pubescent  over  the  seed.  Inner 
bark  mucilaginous  and  medicinal.  Wood  hard  and  strong  but 
splitting  easily  when  dry.  Along  streams,  on  flood  plains  and 
on  hills.  Quebec  to  N.  Dak.,  Fla.,  and  Texas. 

(i.  Ulmus  moutana  With.  Scotch  Elm.  A  large  tree 
with  spreading  branches,  or  in  some  varieties  with  strictly 


Trees  of  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,  inequi¬ 
lateral,  serrate  leaves  and  with  bark  scaling  off  in  plates. 

Trees  similar  to  the  elms  but  with  a  nut-like  fruit  and  the 
flowers  expanding  with  the  leaves. 

1.  Planera  aquatica  (Walt.)  Gmel.  Planertree.  A  small 
tree  with  nearly  glabrous  leaves  growing  in  swamps  and  on 
wet  banks.  Wood  compact,  soft,  weak,  light  brown.  Ind.  to 
Mo.,  Ky.,  N.  Car.,  Fla.,  and  Texas. 


50.  Celtis  (Tourn.)  L.  Hackberry. 

Trees  or  shrubs  with  2-ranked,  siniple,  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  pu¬ 
bescent.  C.  occidentalis. 

1.  Leaves  entire  or  few-toothed,  small.  C.  mississippi- 
ensis. 

1 .  Celtis  occidentalis  L.  (Jommon  Hackberry.  A  medium¬ 
sized  tree  with  rough  bark.  Commonly  much  distorted  with 
“witches  brooms.”  Drupe  sweet  and  edible.  Self-prunes  the 
fruiting  twigs  in  winter.  Wood  heavy,  hard,  strong,  quite 
tough,  greenish-white.  In  dry  soil  and  on  flood  plains.  Que¬ 
bec  to  Man.,  N.  Car:,  Mo.,  Kan.,  and  Okla. 

2.  Celtis  mississippiensis  Bose.  Southern  Hackberry.  A 
medium-sized  tree  with  light  gray,  rough  bark.  Usually  in 
dry  soil.  Va.  to  Ill.,  Mo.,  Kan.,  Fla.,  and  ,Texas. 


I<’ikm>  Manual 


u  l 


Moranvr.  Mulberry  Family. 

Subfamily,  M oratin'. 

51.  Morus  (Tourn.)  L.  Mulberry. 

Trees  or  shrubs  with  alternate,  simple,  2-rankod  leaves  with 
two  prominent  side  ribs  from  the  base,  with  milky  sap,  am] 
with  glabrous  or  pubescent  but  not  downy  twigs. 

Flowers  mouosporangiate ;  fruit  aggregate,  berry-like. 

1.  I , eaves  scabrous  above,  pubescent  beneath.  M.  rubra. 

1.  Leaves  smooth  and  glabrous  on  both  sides,  or  nearly  so. 

M.  alba. 

1.  Morns  rubra  L.  Red  Mulberry.  A  small,  moneeious 
or  dieeious  tree  with  rough  gray  bark,  separating  in  strips. 
Fruit  dark  purple  red,  edible,  delicious.  Wood  rather  heavy, 
hard,  strong,  and  rather  tough;  very  durable  in  contact  with 
the  ground,  very  valuable  for  posts;  used  for  farm  imple 
meats,  in  cooperage,  “acid  wood,”  and  ship  building.  In  rich 
soil.  Vt.  and  Out.  to  Mich.,  8.  Dak.,  Fla.,  and  Texas. 

2.  Morus  alba  L.  White  Mulberry.  A  small  rapid-grow¬ 
ing  tree  with  rough  tight-gray  bark  and  spreading  branches. 
Fruit  edible  but  usually  rather  insipid.  Leaves  used  for 
feeding  silk-worms.  Wood  suitable  for  posts.  Although  grow¬ 
ing  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.  Introduced  from 
the  old  world.  Me.  and  Out.,  to  Fla.  and  Kan. 

52,  Toxylon  Rnf.  Osage-orange. 

Small  trees  with  alternate  simple  entire  leaves,  typical 
axillary  thorns,  and  milky  sap. 

Flowers  dieeious,  the  statu inato  racemose,  the  carpollate 
capitate;  fruit  a  large  spherical,  greenish  or  yellowish  aggre¬ 
gate.  ^  rt  . 

1.  Toxylon  pomfferum  Uaf.  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  lire  wood,  also  for  wagon  making. 
The  thorns  produce  painful  wounds.  Horses  acquire  a  strong 


Trees  op  the  Northern  United  States 


95 


liking  for  the  young  shoots  ancl  eat  them  in  large  quantities 
without  apparent  ill  effects.  Mo.  and  Kan.  to  Texas.  Es¬ 
caped  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  pin- 
nately  straight-veined  dentate  leaves,  with  a  vein  for  each 
tooth,  and  with  prominnt  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  yel¬ 
low.  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  Texas. 

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. 


96 


Field  Manual 


1.  Leaves  green  on  both  sides;  large  trees.  C.  dcntata. 

1.  Leaves  densely  white-tomentose  beneath;  shrubs  or 
small  trees.  C.  pumila. 

1.  Castanea  dentata  (Marsh.)  Borkh.  Chestnut.  A  large 
tree  of  very  rapid  growth  with  rough  bark  in  longitudinal 
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., 
6a.,  and  Ark. 

2.  Castanea  pumila  (L).  Mill.  Chinquapin.  A  shrub  or 
small  tree.  Nut  very  sweet.  Wood  much  like  in  C.  dentata 
but  heavier.  Tn  dry  soil.  N.  J.  to  Ind.,  Mo.,  Fla,  and  Texas. 

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  1 -seeded  coriaceous  nut  (acorn)  in  an  involucrate  cup. 

L  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.  6. 

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.  Q. 

muhlenbergii. 

4.  Shrub  or  low  tree,  leaves  obovate  or  oval ;  seed  edible. 

Q.  privoides. 

5.  Peduncle  as  long  or  shorter  than  the  petioles;  leaves 

gray-tomentulose  beneath.  6. 

5.  Peduncle  much  longer  than  the  petioles;  leaves  vhite- 
tomentulose  beneath.  Q.  bicolor. 


Trees  of  the  Northern  United  States 


97 


6.  Teeth  of  the  leaves  acute  or  mucronulate ;  bark  white, 
flaky;  seed  sweet  and  edible;  fruit  short  peduncled 
or  sometimes  nearly  sessile.  Q.  michauxii. 

6.  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. 

7.  Mature  leaves  pubescent  or  tomentose  below,  lyrate-pin- 

natifid.  9. 

8.  Bark  separating  in  thjn  scales,  light  gray  or  light 

brown;  cup  shallow;  bracts  thick  and  warty.  Q.alba. 

8.  Bark  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.  macroc.arpa. 

10.  Leaves  obovate-obloug,  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. 

12.  Leaves  oblong  or  lanceolate,  tomentulose  beneath.  Q. 

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. 

13.  Leaves  obovate-cuneat.e,  brown-fioccose  beneath;  cup 

deep,  acorn  ovoid.  Q.  marylandica. 

14.  Leaves  white  or  gray-tomentose  below.  1 5. 

14.  Leaves  green  on  both  sides.  17. 

15.  Leaf-lobes  lanceolate  or  linear  lanceolate,  long;  large 

trees.  16. 


9S 


Field  Manual 


15.  Leaf-lobes  triangular-ovate,  short ;  shrubs  or  low  trees. 

Q.  ilicifolia. 

16.  Leaves  rounded  or  obtuse  at  the  base,  3-5  lobed;  lobes 

linear  or  lanceolate,  often  falcate.  Q.  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  }-l  in.  broad;  acorn  ovoid  or  elon¬ 

gated.  Q.  rubra. 

20.  Leaves  shining  deeply  pinnatifid;  cup  Li  in.  broad; 

acorn  subglobose  or  ovoid:  Q.  palustris. 

Chestnut  Oaks. 

1.  Quercus  prinus  L.  Rock  Chestnut  Oak.  A  large 

tree  with  brown  bark,  ridged  close  or  slightly  flaky.  Leaves 
oblong,  oblong-lenceolate,  or  obovate,  coarsely  crenate,  glab¬ 
rous  above,  finely  gray-tomentulose  beneath,  petioles  slender; 
cup  hemispheric,  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-pruncs,  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  faky  white  bark.  Leaves  obovate  or  broadly  oblong, 
crenately  toothed,  the  teeth  often  mucronulate,  4-8  in  long, 
cup  depressed-hemispheric,  short-peduncled,  1-1}  in.  broad; 
acorns  ovoid,  about  3  times  as  high  as  the  cup,  sweet  and 

edible.  Wood  valuable  like  the  White  Oak.  In  moist  soil. 

Bel.  to  Tnd.,  Mo.,  Ark.,  Fla.,  and  Texas. 


Trees  of  the  Northern  United  States 


99 


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  iu  dry 
soil,  commonly  on  limestone  ridges.  Vt.  and  Ont.  to  Minn., 
Ala.,  Neb.,  and  Texas. 

4.  Quercus  prinoides  Willd.  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  Texas. 

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  glabrous  above,  densely  white-tomentulose  beneath ;  ped¬ 
uncles  of  the  hemisphere  cup  2-5  times  as  long  as  the  petioles; 
acorn  oblong  ovoid,  seed  rather  sweet.  Self-prunes.  Wood 
similar  in  value  
…[truncated]