Studies of Trees | Page 8

tree with a straight trunk.
Range: Eastern North America.
Soil and location: Rich, moist soil.
Enemies: In cities it is very often attacked by sucking insects.
Value for planting: The white ash grows rapidly. On account of its insect enemies in cities, it should be used more for forest planting and only occasionally for ornament.
Commercial value: It has a heavy, tough, and strong wood, which is valuable in the manufacture of cooperage stock, agricultural implements, and carriages. It is superior in value to the black ash.
Other characters: The bark is gray. The flowers appear in May.
Comparisons: The white ash is apt to be confused with the black ash (Fraxinus nigra), but differs from the latter in having a lighter-colored bud. The bud of the black ash is black. The bark of the white ash is darker in color and the terminal twigs are more flattened than those of the black ash.
[Illustration: FIG. 23.--Leaf of White Ash.]
SUGAR MAPLE (Acer saccharum)
Distinguishing characters: The *bud is sharp-pointed*, scaly, and reddish brown. Fig. 24.
[Illustration: FIG. 24.--Twig of the Sugar Maple.]
Leaf: Has sharp points and round sinus. Fig. 25.
Form and size: The crown is oval when the tree is young and round in old age. Fig. 26.
Range: Eastern United States.
Soil and location: Moist and deep soil, and cool, shady positions.
Enemies: Subject to drouth, especially in cities. Is attacked by the sugar maple borer and the maple phenacoccus, a sucking insect.
Value for planting: Its rich and yellow color in the fall, and the fine spread of its crown make it a desirable tree for the lawn, especially in the country.
Commercial value: Its wood is hard and takes a good polish; used for interior finish and furniture. The tree is also the source of maple sugar. Fig. 27.
Other characters: The bark is smooth in young trees and in old trees it shags in large plates. The flowers appear in the early part of April.
Other common names: The sugar maple is sometimes called rock maple or hard maple.
SILVER MAPLE (Acer saccharinum)
Distinguishing characters: The tips of the *twigs curve upwards* (Fig. 28), the bark is scaly, and the leaves are very deeply cleft and are silvery on the under side.
[Illustration: FIG. 25.--Leaf of Sugar Maple.]
Leaf: Deeply cleft and silvery under side. Fig. 29.
Form and size: A large tree with the main branches separating from the trunk a few feet from the ground. The terminal twigs are long, slender, and drooping.
Range: Eastern United States.
Soil and location: Moist places.
Enemies: The leopard moth, a wood-boring insect, and the cottony-maple scale, a sucking insect.
[Illustration: FIG. 26.--The Sugar Maple.]
Value for planting: Grows too rapidly and is too short-lived to be durable.
Commercial value: Its wood is soft, weak, and little used.
Other characters: The bark is light gray, smooth at first and scaly later on. The scales are free at each end and attached in the center. The flowers appear before the leaves in the latter part of March or early April.
[Illustration: FIG. 27.--Tapping the Sugar Maple.]
Other common names: The silver maple is sometimes known as soft maple or white maple.
RED MAPLE (Acer rubrum)
[Illustration: FIG. 28.--Terminal Twig of Silver Maple.]
Distinguishing characters: The *bark is smooth and light gray*, like that of the beech, on the upper branches in older trees, and in young trees over the whole trunk. Fig. 30. The buds are in clusters, and the terminal twigs, Fig. 31, are quite red.
[Illustration: FIG. 29.--Leaf of the Silver Maple.]
Leaf: Whitish underneath with three-pointed lobes. Fig. 32.
Form and size: A medium-sized tree with a narrow, round head.
Range: Eastern North America.
Soil and location: Prefers moist places.
Enemies: Leaf blotches (Rhytisma acerinum) which, however, are not very injurious.
Value for planting: Suitable as a shade tree for suburban streets. Its rich red leaves in the fall make it attractive for the lawn.
[Illustration: FIG. 30.--Bark of the Red Maple.]
Commercial value: Its wood is heavy, close-grained, and takes a good polish. Used for furniture and fuel.
Other characters: The bud is small, round, and red. The flowers appear before the leaves are out in the early part of April.
[Illustration: FIG. 31.--Twig of the Red Maple.]
[Illustration: FIG. 32.--Leaf of the Red Maple.]
Other common names: The red maple is sometimes known as swamp maple.
[Illustration: FIG. 33.--Twig of Norway Maple.]
Comparisons: The red maple is apt to be confused with the silver maple, but the latter can be distinguished by its turned-up twigs and scaly bark over the whole trunk of the tree, which presents a sharp contrast to the straight twig and smooth bark of the red maple. The latter has a bark similar to the beech, but its branches are opposite, while those of the beech are alternate.
NORWAY MAPLE (Acer platanoides)
Distinguishing characters: The bud, Fig. 33, is *oval and reddish-brown* in color; when taken off, a *milky juice exudes*. The bark is close. Fig. 34
[Illustration: FIG. 34.--Bark of Norway Maple.]
Leaf: Like the leaf of the sugar maple but thicker