Studies of Trees Part 9

Form and size: The tree grows in an irregular form to large size, with its branches rather slender as compared with the white oak and with a more open and narrow crown.

Range: Eastern North America.

Soil and location: It will grow in poor soils but does best where the soil is rich and well drained.

Enemies: None of importance.

Value for planting: The black oak is the poorest of the oaks for planting and is rarely offered by nurserymen.

Commercial value: The wood is heavy, hard and strong, but checks readily and is coa.r.s.e grained. It is of little value except for fuel. The bark is used for tannin.

Other common names: _Yellow oak_.

Comparisons: The black oak might sometimes be confused with the _red_ and _scarlet oaks_. The yellow, bitter inner bark will distinguish the black oak from the other two. The light-colored, smooth bark of the red oak and the dark, ridged bark of the black oak will distinguish the two, while the bark of the scarlet oak has an appearance intermediate between the two. The buds of the three species also show marked differences. The buds of the black oak are covered with hairs, those of the scarlet oak have fewer hairs and those of the red are practically free from hairs. The leaves of each of the three species are distinct and the growth habits are different.

RED OAK (_Quercus rubra_)

Distinguishing characters: The *bark* is perpendicularly fissured into long, _smooth, light gray strips_ giving the trunk a characteristic *pillar effect* as in Figs. 61 and 94. It has the straightest trunk of all the oaks. The leaves possess _more lobes_ than the leaves of any of the other species of the black oak group, see Fig. 62. The acorns, the largest among the oaks, are semispherical with the cups extremely shallow. The buds are large and sharp pointed, but not as large as those of the black oak. They also have a few fine hairs on their scales, but are not nearly as downy as those of the Black oak.

[Ill.u.s.tration: FIG. 61--Bark of Red Oak.]

Form and size: The red oak is the largest of the oaks and among the largest of the trees in the northern forests. It has a straight trunk, free from branches to a higher point than in the white oak, see Fig. 94. The branches are less twisted and emerge at sharper angles than do those of the white oak.

Range: It grows all over Eastern North America and reaches north farther than any of the other oaks.

Soil and location: It is less fastidious in its soil and moisture requirements than the other oaks and therefore grows in a great variety of soils. It requires plenty of light.

[Ill.u.s.tration: FIG. 62.--Leaf and Fruit of Red Oak.]

Enemies: Like most of the other oaks, this species is comparatively free from insects and disease.

Value for planting: The red oak grows faster and adapts itself better to poor soil conditions than any of the other oaks and is therefore easy to plant and easy to find in the nurseries. It makes an excellent street tree, is equally desirable for the lawn and is hardly surpa.s.sed for woodland planting.

Commercial value: The wood is hard and strong but coa.r.s.e grained, and is used for construction timber, interior finish and furniture. It is inferior to white oak where strength and durability are required.

PIN OAK (_Quercus pal.u.s.tris_)

Distinguishing characters: Its method of *branching* will characterize the tree at a glance. It develops a well-defined _main_ ascending _stem_ with numerous _drooping_ side _branches_ as in Fig. 63. The buds are very small and sharp pointed and the leaves are small as in Fig. 64. The bark is dark, firm, smooth and in close ridges. The acorn is small and carries a light brown, striped nut, wider than long and bitter. The cup is shallow, enclosing only the base of the nut.

[Ill.u.s.tration: FIG. 63.--Pin Oaks in Winter.]

Form and size: The pin oak is a medium-sized tree in comparison with other oaks. It develops a tall, straight trunk that tapers continuously through a pyramidal crown of low, drooping tender, branches.

Range: Eastern North America.

Soil and location: It requires a deep, rich, moist soil and grows naturally near swamps. Its roots are deep and spreading. The tree grows rapidly and is easily transplanted.

Enemies: None of importance.

Value for planting: The pin oak is an extremely graceful tree and is therefore extensively used for planting on lawns and on certain streets where the tree can find plenty of water and where conditions will permit its branches to droop low.

Commercial value: The wood is heavy and hard but coa.r.s.e grained and liable to check and warp. Its princ.i.p.al use is in the construction of houses and for shingles.

[Ill.u.s.tration: FIG. 64.--Leaf and Fruit of Pin Oak.]

CHESTNUT (_Castanea dentata_)

Distinguishing characters: The *bark* in young trees is smooth and of a marked reddish-bronze color, but when the tree grows older, the bark breaks up into *diamond-shaped ridges*, sufficiently characteristic to distinguish the tree at a glance, see Fig. 65. A close examination of the _terminal twig_ will show _three ridges_ and _two grooves_ running down along the stem from the base of each leaf or leaf-scar. The twig has no true terminal bud. The fruit, a large, round *bur*, p.r.i.c.kly without and hairy within and enclosing the familiar dark brown, sweet edible nuts is also a distinguishing mark of the tree.

Leaf: The leaves are distinctly long and narrow. They are from 6 to 8 inches long.

Form and size: The chestnut is a large tree with a ma.s.sive trunk and broad spreading crown. The chestnut tree when cut, sprouts readily from the stump and therefore in places where the trees have once been cut, a group of two to six trees may be seen emerging from the old stump.

[Ill.u.s.tration: FIG. 65.--Trunk of Chestnut Tree.]

Range: Eastern United States.

Soil and location: It will grow on rocky as well as on fertile soils and requires plenty of light.

Enemies: During the past nine years nearly all the chestnut trees in the United States have been attacked by a fungus disease (_Diaporthe parasitica_, Mur.) which still threatens the entire extinction of the chestnut trees in this country. No remedy has been discovered and all affected trees should be cut down and the wood utilized before it decays and becomes worthless. No species of chestnut tree is entirely immune from this disease, though some species are highly resistant.

Value for planting: The chestnut is one of the most rapidly growing hardwood trees but, on account of its disease, which is now prevalent everywhere, it is not wise to plant chestnut trees for the present.

Commercial value: The wood is light, not very strong and liable to warp.

It is durable when brought in contact with the soil and is therefore used for railroad ties, fence-posts, poles, and mine timbers. It is also valuable for interior finish in houses and for fuel. Its bark is used in the manufacture of tanning extracts and the nuts are sold in cities in large quant.i.ties.

CHAPTER III

HOW TO IDENTIFY TREES--(Continued)

GROUP IX. THE HICKORIES, WALNUT AND b.u.t.tERNUT

How to tell them from other trees and from each other: The hickory trees, though symmetrical, have a rugged _appearance_ and the _branches_ are so st.u.r.dy and black as to give a special distinction to this group. The _buds_ are different from the buds of all other trees and sufficiently characteristic to distinguish the various species of the group. The _bark_ is also a distinguishing character.

The walnut and b.u.t.ternut have _chambered piths_ which distinguish them from all other trees and from each other.

s.h.a.gBARK HICKORY (_Hicoria ovata_)

Distinguishing characters: The yellowish brown *buds* nearly as large as those of the mockernut hickory, _are each provided with two long, dark, outer scales_ which stand out very conspicuously as shown in Fig. 67. The *bark* in older specimens *s.h.a.gs* off in rough strips, sometimes more than a foot long, as shown in Fig. 68. These two characters will readily distinguish the tree at all seasons of the year.