TREES andodor.
smooth when the tree is young, but scales off in thin fragments as the tree beolder. ‘The bark resembles that of the black bireh but can guished from it by the presence of conspicuous comes be distinlenticels (breathing structures).
4. American Gray Birch (Betula populifolva Marsh). ‘The twigs of the gray birch are slender and flexible. They are very tough. ‘The new twigs are The buds extend at an angle scmewhat less than 45° and the twigs are bent where the buds are attached (Fig. 58).
characterized by its sprout rough to the touch. = ; :
eHeSnNUT The gray lirch is TWIG FIG.
67.
Twigs of recent oyowth, that is, it seems growthhave1idges k : to have several trunks extending down- :
rditrom the leat. Waich start out close tosears gether at the ground or ‘This birch grows in very poor soil, and we associate it near it (Fig. 59). with scrub oaks, sumachs, barberries, red cedars and other low trees and shrubs bordering The white bark of the tree is chalky to the touch; it does not peel from the trunk but remains smooth as forests and occupying waste land. the tree grows old. There are conspicuous triangles of dark color on the trunk below the points of insertion of the branches. Canoe, Paper or White Birch (Betula papyrifera Marsh) can be distinguished AND FORESTRY S7 . . s .
The broken twigs have a peculiarly pungent, bitter flavor The bark of the trunk is reddish brown and GRAY BIRCH FIG.
58.
GrayBirchtwigsarerough to the touch and are bent at the points where the buds grow. Rigid, staminate catkinsshowtheirwintercondition
SS AMERICAN MUSEUM GUIDE LEAFLETS from the gray birch by the fact that the white shining bark of the trunk continually splits into thin layers and is frayed in the wind. ‘The white birch grows to great size. Black Birch (Betula lenta 1.) has twigs of golden brown color and aromatic flavor, FIG.60.YELLOWBIRCH The bark may be frayed into a tangle of ribbons differing from those of the gray birch in being brittle instead of tough. The tree can be distinguished also by the bark of the trunk, which is likely to be smooth and reddish brown like that of the cherry, but lacks the horizontal lenticels of the FIG. 69. GRAY BIRCH IN WINTER cherry; it never frays into strips when old.
CO We) TREES AND FORESTRY FIG.61.WHITEELMTWIGS Some results of a gray squirrel’s pruning. He bit off the twigs and ate the flower buds. In the spring the tree seemed in as full leaf as its neighbors Yellow Birch (Betula lutea Michx.). ‘The twigs of yellow birch are less aromatic than those of black birch. The buds are sharppointed, light chestnut brown and about onefourth inch long. The bark is vellow and separates into thin pieces (Fig. 60). 5. American or White Elm (U/mus americana L.). The twigs of the white elm (Fig. 61) are difficult of recognition. They are smooth and dark-colored, almost lacking ‘the white spots so conspicuous on many twigs. ‘The small brown buds are scaly and pointed. The alternate branches are given off at right and left in a horizontal plane, are about equal in length, and, although they are not quite at right angles and not opposite like those of red maple, nevertheless at first glance they give the appearance of a miniature telegraph pole with cross-bars; sprays of this character are conspicuous near the top of the tree. ‘The white elm is easily recognized in winter by the vase shape of the tree and the delicacy of the spray.
Slippery Elm (Ulmus fulva Michx.) can be distinguished from the white elm by the large size and downy character of its buds and by its mucilaginous inner bark.
6. Linden or Basswood (T'lia americana L.). FIG.
62.
BASSWOOD Smoothandbrown twigs with fat reddish brown buds
90 AMERICAN MUSEUM GUIDE LEAFLETS The twigs are smooth and brown, not conspicuously dotted with white. The fat reddish brown buds have few scales and project from the stem at an angle of 45°. The terminal bud is often lacking. The twigs may show the bending at the points of attachment of buds as in the gray birch (Fig. 62). The bark on the trunk is dark and furrowed. ‘The basswood sprouts BN Staminate Flowers FIG.683,TWIGSOFSMOOTHALDER The buds are stemmed. The drawing shows also the winter condition of staminate and pistillate flowers out slender branches directly from the trunk. 7. Common Alder (Alnus rugosa Spreng.). The brittle twigs are grayish brown and smooth, with scattered light spots. Alder can be known by the fact that the smooth .. « wuice wickonyorwiel oval buds are on short stems of their own. Thetterminal bud isalenes rt. . . - .
The buds project at an angle of 45° or less Jargest. Tough, smooth twigs (Fig. 63). This alder and the more north- showing conspicuous lenticels
TREES AND FORESTY 91 ern species, Speckled Alder (Alnus incana Willd.), grow along brooks and about marshes. The twigs of the latter can be distinguished from those of the former by their downy appearance and by the large number of light-colored lenticels which give the name “Speckled” to the species. ‘These alders seldom reach a height of more than twelve to fourteen feet.
8. Common Locust (Robinia pseudacacia L.). The recognition of locust twigs presents no difficulty. The twigs are slender, smooth and brown, ridged lengthwise and furnished with pairs of thorns. Between the individual! thorns of each pair is a bud almost hidden in the center of a leaf scar: each leaf stem of the locust is hollow at its base and fits over a bud, so that no buds are visible until the leaves have fallen. The bark of the tree is rough and furrowed.
II. Hickory and Oak: Trees with more or less stout and stiff twigs having alternate buds and dark bark.
1. Mockernut or White Hickcry (/:coria alba Britt.). This hickory can be recognized by the large buds which are hard and round with few downy brown scales. The terminal bud is always largest; the lateral buds extend at an angle of 45° or more (Fig. 64). ‘The tough twigs are smooth and reddish brown, and have conspicuous white lenticels. The older twigs are dark gray. The mockernut hickory is a large tree with bark showing wavy furrows. Shagbark Hickory (Hicoria ovata Britt.) has buds with dark scales. The bark on the trunk “‘shags’’ off whenold.
Pignut Hickory (Hicoria glabra Britt.) has twigs that are smooth and greenish brown; they may be somewhatangled.
2. White Oak (Quercus alba L.) can FIG.66.OAKBUDS Braided in appearance due tothearrangementofthescales.
white oak buds are rounded; blackoak,pointed.
FIG, WOOD TWIG Conical brown buds cente scars AMERICAN MUSEUM GUIDE LEAFLETS be distinguished by its rounded buds, which have a braided appearance given by the many closely overlap- | ping scales (Fig. 65, twig at left). Lateral buds are crowded about the terminal bud, producing a cluster. The leaf scars project from the twig. The leaves, which have rounded lobes, are likely to remain on the tree throughout the winter. The “sweet’’ acorns are in shallow, rough cups. The bark on the trunk of the tree is light-colored and rough. 66.
BUTTONare in the rs of the leaf FIG.67.THETRUNKOFAYOUNGBUTTON- WOOD TREE Black Oak (Quercus velutina Lam.). The large buds (Fig. 65, twiz at right) are sharp-pointed and somewhat downy. ‘The twigs are smooth and have a bitter taste. The “bitter’’ acorns are in deep cups. The bark on the trunk is dark in color. “Oak apples”’ are found on black oaks.
The white oak, swamp white oak, chestnut oak, post oak and some others, are white oaks, recognized by the light bark of their trunks and the rounded lobes of their leaves. ‘They are difficult of distinction from one another in their winter condition.
TREES AND FORESTRY 93 The black oak, scarlet oak, red oak, scrub oak and a few others, are black oaks known by the dark bark of their trunks and by the pointed lobes of their leaves. They also are distinguished from one another with difficulty in winter. II. Willow, Poplar, Buttonwood: Trees whose light-colored twigs have FIG.68.BUTTERNUTTWIG Shows leaf buds only. The lateral leaf buds are stemmed alternate buds and are more or less slender andflexible.
1. White Willow or Golden Osier (Salix alba var. vitellina). The twigs of this willow are light yellow in color, smooth, tough, and very flexible. The pointed buds hug the stem; each is covered by a single scale in the form of a peaked cap which may look as though empty at FIG,69.BUTTERNUTTWIGS Showingstaminateflowerbuds
94 AMERICAN MUSEUM GUIDE LEAFLETS the top. This 7/4 , ay \ tree, naturaliS: Me) ized from Eu- . i 4 2 4 i rope, 1S Very vA | Ai 8 ( 5 ae along i WN AA ms Le ING Seen --Bark lass streams anc ) A Hf, marshes. ‘The 4. Te a 1 -~-Wood \\ 4a many native 5 y . ° a 4 (qi varieties ot i i Y 3 :
\ % 4 q willow are i < an Pdi “7. > | ISS S 0 } difficult of rec- } = ~Chambered SS Veil? an +1: :
\ iA 4) = ognition even i — Pith \ AA <Sas0 A ox \ | aa" when they have H = We flowers or 5 leaves. o—t 2. Ameri- FIG. 71. BUTTERNUT TWIG can Aspen Longitudinal section to show the (Populus trem- chambered pith uloidesMichx.).
The twigs of the American aspen are greenish gray and smooth. ‘The pointed buds are long and covered with glossy, gummy scales. ‘The tree is a small one with smooth greenish gray bark. Larze-toothed Aspen (Populus grandidentata FIG. 70. BLACK WALNUT Michx.) has the same smooth greenish gray bark Leaf and _ flower as has the American aspen, but is a tree of buds. The leaf scars smaller size. Its pointed buds are downy leche eS SaO Pe ues instead of smooth and they extend at right angles conspicuous in butter- é ; : 2 = eat from the twig.
Balsam Poplar (Populus balsamifera L.) can be recognized by its coarse, ridged twigs and by the large sticky buds which have an unusually sweet odor. 3. Sycamore, Plane-tree, or Buttonwood (Platanus occidentalis L.). The light-colored smooth twigs are rigid in appearance. The conical pre buds are in the centers of the leaf scars, being formed within the hollow bases of stems and not showing until the leaves fall (Fig. 66). The outer board-like scale covers light-brown silky scales of great beauty. The tree can be known by the bark which comes off in plates, leaving smooth ereen or white spots (Fig. 67). The balls of fruit hang on the tree all winter.