Studies of Trees Part 11

Form and size: The tulip tree is one of the largest, stateliest and tallest of our trees.

Range: Eastern United States.

Soil and location: Requires a deep, moist soil.

Enemies: Comparatively free from insects and disease.

Value for planting: The tree has great value as a specimen on the lawn but is undesirable as a street tree because it requires considerable moisture and transplants with difficulty. It should be planted while young and where it can obtain plenty of light. It grows rapidly.

Commercial value: The wood is commercially known as _whitewood_ and _yellow poplar_. It is light, soft, not strong and easily worked. It is used in construction, for interior finish of houses, woodenware and s.h.i.+ngles. It has a medicinal value.

Other characters: The _flower_, shown in Fig. 75, is greenish yellow in color, appears in May and resembles a tulip; hence the name tulip tree. The _fruit_ is a cone.

Other common names: _Whitewood_; _yellow poplar_; _poplar_ and _tulip poplar_.

SWEET GUM (_Liquidambar styraciflua_)

[Ill.u.s.tration: FIG. 75.--Leaf and Flower of the Tulip Tree.]

Distinguis.h.i.+ng characters: The _persistent, spiny_, long-stemmed round *fruit*; _the corky growths on the_ *twigs*, the characteristic _star-shaped_ *leaves* (Fig. 76) and the very s.h.i.+ny greenish brown buds and the perfect symmetry of the tree are the chief characters by which to identify the species.

Form and size: The sweet gum has a beautiful symmetrical shape, forming a true monopodium.

[Ill.u.s.tration: FIG. 76.--Leaf and Fruit of the Sweet Gum. Note the corky ridges along the twig.]

Range: From Connecticut to Florida and west to Missouri.

Soil and location: Grows in any good soil but prefers low wet ground. It grows rapidly and needs plenty of light.

Enemies: Is very often a favorite of leaf-eating caterpillars.

Value for planting: The tree is sought for the brilliant color of its foliage in the fall, and is suitable for planting both on the lawn and street. In growing the tree for ornamental purposes it is important that it should be frequently transplanted in the nursery and that it be transported with burlap wrapping around its roots.

Commercial value: The wood is reddish brown in color, tends to splinter and is inclined to warp in drying. It is used in cooperage, veneer work and for interior finish.

Other characters: On the smaller branches there are irregular developments of cork as shown in Fig. 76, projecting in some cases to half an inch in thickness.

Other common names: _Red gum_.

Comparisons: The _cork elm_ is another tree that possesses corky ridges along its twigs, but this differs from the sweet gum in wanting the spiny fruit and its other distinctive traits.

AMERICAN LINDEN (_Tilia Americana_)

[Ill.u.s.tration: FIG. 77.--Bud of the Linden Tree.]

Distinguis.h.i.+ng characters: The great distinguis.h.i.+ng feature of any linden is the *one-sided* character of its *bud* and *leaf*. The bud, dark red and conical, carries a sort of protuberance which makes it extremely one sided as shown in Fig. 77. The leaf, Fig. 78, is heart-shaped with the side nearest the branch largest.

[Ill.u.s.tration: FIG. 78.--Leaves and Flowers of the European Linden.]

Form and size: The American Linden is a medium-sized tree with a broad round head.

Range: Eastern North America and more common in the north than in the south.

Soil and location: Requires a rich, moist soil.

[Ill.u.s.tration: FIG. 79.--European Linden Tree.]

[Ill.u.s.tration: FIG. 80.--Bud of the Umbrella Tree.]

Enemies: Its leaves are a favorite food of caterpillars and its wood is frequently attacked by a boring insect known as the _linden borer_ (_Saperda vest.i.ta_).

Value for planting: The linden is easily transplanted and grows rapidly.

It is used for lawn and street planting but is less desirable for these purposes than the European species.

Commercial value: The wood is light and soft and used for paper pulp, woodenware, cooperage and furniture. The tree is a favorite with bee keepers on account of the large quant.i.ties of nectar contained in its flowers.

Other characters: The _fruit_ is like a pea, gray and woody. The _flowers_ appear in early July, are greenish-yellow and very fragrant.

Other common names: _Ba.s.s-wood_; _lime-tree_; _whitewood_.

Comparisons: The _European lindens_, Fig. 79, of which there are several species under cultivation, differ from the native species in having buds and leaves smaller in size, more numerous and darker in color.

THE MAGNOLIAS

The various species of magnolia trees are readily distinguished by their buds. They all prefer moist, rich soil and have their princ.i.p.al value as decorative trees on the lawn. They are distinctly southern trees; some species under cultivation in the United States come from Asia, but the two most commonly grown in the Eastern States are the cuc.u.mber tree and the umbrella tree.

[Ill.u.s.tration: FIG. 81.--Bark of the Black Locust.]

CUc.u.mBER TREE (_Magnolia ac.u.minata_)

Distinguis.h.i.+ng characters: The *buds* are _small_ and _slender_ compared with those of the other magnolia trees and are _covered_ with small silvery silky _hairs_. The *habit* of the tree is to form a straight axis of great height with a symmetrical ma.s.s of branches, producing a perfect monopodial crown. The tree is sometimes known as _mountain magnolia_.

UMBRELLA TREE (_Magnolia tripetala_)

Distinguis.h.i.+ng characters: The _buds_, Fig. 80, are extremely _long_, often one and a half inches, have a _purple color_ and _are smooth_.

The tree does not grow to large size and produces an open spreading head. Its leaves, twelve to eighteen inches long, are larger than those of the other magnolia trees. The tree is sometimes called _elkwood_.

BLACK LOCUST (_Robinia pseudacacia_)

Distinguis.h.i.+ng characters: The *bark* of the trunk is _rough_ and _deeply ridged_, as shown in Fig. 81. The *buds* are _hardly noticeable_; the twigs sometimes bear small spines on one side. The leaves are large, compound, and fern-like. The individual leaflets are small and delicate.

Form and size: The locust is a medium-sized tree developing a slender straight trunk when grown alongside of others; see Fig. 82.