CHAPTER III

HOW TO IDENTIFY TREES--(Continued)

GROUP IX. THE HICKORIES, WALNUT AND BUTTERNUT

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 sturdy 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 butternut have _chambered piths_ which distinguish

them from all other trees and from each other.

SHAGBARK 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 *shags* 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.

[Illustration: FIG. 66.--A Shagbark Hickory Tree.]

Leaf: The leaf is compound, consisting of 5 or 7 leaflets, the terminal

one generally larger.

Form and size: A tall, stately tree--the tallest of the hickories--of

rugged form and fine symmetry, see Fig. 66.

Range: Eastern North America.

Soil and location: The shagbark hickory grows in a great variety of

soils, but prefers a deep and rather moist soil.

Enemies: The _hickory bark borer_ (_Scolytus quadrispinosus_) is its

principal enemy. The insect is now killing thousands of hickory

trees in the vicinity of New York City and on several occasions has

made its appearance in large numbers in other parts of the country.

Value for planting: It is difficult to transplant, grows slowly and is

seldom found in nurseries.

[Illustration: FIG. 67.--Bud of the Shagbark Hickory.]

Commercial value: The wood is extremely tough and hard and is used for

agricultural implements and for the manufacture of wagons. It is

excellent for fuel and the nuts are of great value as a food.

Other characters: The fruit is a nut covered by a thick husk that

separates into 4 or 5 segments. The kernel is sweet.

Other common names: _Shellbark hickory_.

MOCKERNUT HICKORY (_Hicoria alba_)

[Illustration: FIG. 68.--Bark of the Shagbark Hickory.]

Distinguishing characters: The *bud* is the largest among the

hickories--nearly half an inch long--is hard and oval and covered

with _yellowish brown_ downy _scales_ which _do not project_ like

those of the shagbark hickory, see Fig. 69. The twigs are extremely

coarse. The *bark* is very tight on the trunk and branches and has a

_close_, hard, _wavy_ appearance as in Fig. 70.

Leaf: The leaf consists of 5, 7 or 9 leaflets all of which are large and

pubescent and possess a distinct resinous odor.

Form and size: A tall tree with a broad spreading head.

Range: Eastern North America.

Soil and location: The mockernut hickory grows on a great variety of

soils, but prefers one which is rich and well-drained.

Enemies: The same as for the shagbark hickory.

Value for planting: It is not commonly planted.

Commercial value: The wood is similar to that of the shagbark hickory

and is put to the same uses.

Other characters: The fruit is a nut, larger and covered with a shell

thicker than that of the shagbark. The husk is also thicker and

separates into four segments nearly to the base. The kernel is small

and sweet.

Other common names: _Bigbud hickory_; _whiteheart hickory_.

Comparisons: The _pignut hickory_ (_Hicoria glabra_), sometimes called

broom hickory or brown hickory, often has a shaggy bark, but differs

from both the shagbark and the mockernut hickory in possessing buds

very much smaller, twigs more slender and leaflets fewer. The nut

has a thinner husk which does not separate into four or five

segments. The tree prefers drier ground than the other hickories.

[Illustration: FIG. 69.--Bud of the Mockernut Hickory.]

The _bitternut_ (_Hicoria minima_) can be told from the mockernut

and other species of hickory by its bud, which has no scales at all.

The color of its bud is a characteristic orange yellow. The bark is

of a lighter shade than the bark of the mockernut hickory and the

leaflets are more numerous than in any of the hickories, varying

from 7 to 11. Its nuts are bitter.

BLACK WALNUT (_Juglans nigra_)

Distinguishing characters: By cutting a twig lengthwise, it will be seen

that its *pith* is divided into little _chambers_ as shown in Fig.

71. The bud is dark gray and satiny. The bark is dark brown and

deeply ridged and the fruit is the familiar round walnut.

[Illustration: FIG. 70.--Bark of the Mockernut Hickory.]

Form and size: A tall tree with a spreading crown composed of stout

branches. In the open it grows very symmetrically.

Range: Eastern United States.

Soil and location: The black walnut prefers a deep, rich, fertile soil

and requires a great deal of light.

Enemies: The tree is a favorite of many caterpillars.

Value for planting: It forms a beautiful spreading tree on open ground,

but is not planted to any extent because it is hard to transplant.

It grows slowly unless the soil is very deep and rich, develops its

leaves late in the spring and sheds them early in the fall and

produces its fruit in great profusion.

Commercial value: The wood is heavy, strong, of chocolate brown color

and capable of taking a fine polish. It is used for cabinet making

and interior finish of houses. The older the tree, usually, the

better the wood, and the consumption of the species in the past has

been so heavy that it is becoming rare. The European varieties which

are frequently planted in America as substitutes for the native

species yield better nuts, but the American species produces better

wood.

[Illustration: FIG. 71.--Twig of the Black Walnut. Note the large

chambers in the pith.]

[Illustration: FIG. 72.--Twig of the Butternut. Note the small chambers

in the pith.]

Other characters: The _fruit_ is a large round nut about two inches in

diameter, covered with a smooth husk which at first is dull green

in color and later turns brown. The husk does not separate into

sections. The kernel is edible and produces an oil of commercial

value.

The _leaves_ are compound and alternate with 15 to 23 leaflets to

each.

Comparisons: The _butternut_ (_Juglans cinerea_) is another tree that

has the pith divided into little chambers, but the little chambers

here are shorter than in the black walnut, as may be seen from a

comparison of Figs. 71 and 72. The bark of the butternut is light

gray while that of the black walnut is dark. The buds in the

butternut are longer than those of the black walnut and are light

brown instead of gray in color. The form of the tree is low and

spreading as compared with the black walnut. The fruit in the

butternut is elongated while that of the black walnut is round. The

leaves of the butternut have fewer leaflets and these are lighter in

color.

GROUP X. TULIP TREE, SWEET GUM, LINDEN, MAGNOLIA, LOCUST, CATALPA,

DOGWOOD, MULBERRY AND OSAGE ORANGE

TULIP TREE (_Liriodendron tulipifera_)

Distinguishing characters: There are four characters that stand out

conspicuously in the tulip tree--the *bud*, the *trunk*, the

persistent *fruit cups* and the wedged *leaf*.

The bud, Fig. 74, about three-quarters of an inch long, is covered

by two purplish scales which lend special significance to its whole

appearance. The trunk is extremely individual because it rises stout

and shaft-like, away above the ground without a branch as shown in

Fig. 73. The tree flowers in the latter part of May but the cup that

holds the fruit persists throughout the winter. The leaf, Fig. 75,

has four lobes, is nearly as broad as it is long and so notched at

the upper end that it looks different from any other leaf.

[Illustration: FIG. 73.--The Tulip Tree.]

[Illustration: FIG. 74.--Bud of the Tulip Tree.]

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 shingles. 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_)

[Illustration: FIG. 75.--Leaf and Flower of the Tulip Tree.]

Distinguishing characters: The _persistent, spiny_, long-stemmed round

*fruit*; _the corky growths on the_ *twigs*, the characteristic

_star-shaped_ *leaves* (Fig. 76) and the very shiny 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.

[Illustration: 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_)

[Illustration: FIG. 77.--Bud of the Linden Tree.]

Distinguishing characters: The great distinguishing 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.

[Illustration: 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.

[Illustration: FIG. 79.--European Linden Tree.]

[Illustration: 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 vestita_).

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 quantities 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: _Bass-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 principal 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 cucumber tree and

the umbrella tree.

[Illustration: FIG. 81.--Bark of the Black Locust.]

CUCUMBER TREE (_Magnolia acuminata_)

Distinguishing 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 mass of branches, producing

a perfect monopodial crown. The tree is sometimes known as _mountain

magnolia_.

UMBRELLA TREE (_Magnolia tripetala_)

Distinguishing 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_)

Distinguishing 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.

Range: Canada and United States.

Soil and location: The locust will grow on almost any soil except a wet,

heavy one. It requires plenty of light.

Enemies: The _locust borer_ has done serious damage to this tree. The

grubs of this insect burrow in the sapwood and kill the tree or make

it unfit for commercial use. The _locust miner_ is a beetle which is

now annually defoliating trees of this species in large numbers.

Value for planting: It has little value for ornamental planting.

Commercial value: Though short-lived, the locust grows very rapidly. It

is extremely durable in contact with the soil and possesses great

strength. It is therefore extensively grown for fence-posts and

railroad ties. Locust posts will last from fifteen to twenty years.

The wood is valuable for fuel.

[Illustration: FIG. 82.--Black Locust Trees.]

Other characters: The _flowers_ are showy pea-shaped panicles appearing

in May and June. The _fruit_ is a small pod.

Other common names: _Yellow locust_; _common locust_; _locust_.

Comparisons: The _honey locust_ (_Gleditsia triacanthos_) can be told

from the black locust by the differences in their bark. In the honey

locust the bark is not ridged, has a sort of dark iron-gray color

and is often covered with clusters of stout, sharp-pointed thorns as

in Fig. 83. The fruit is a large pod often remaining on the tree

through the winter. This tree has an ornamental, but no commercial

value.

[Illustration: FIG. 83.--Bark of the Honey Locust.]

HARDY CATALPA (_Catalpa speciosa_)

Distinguishing characters: The tree may be told by its *fruit*, which

hang in long slender pods all winter. The leaf-scars appear on the

stem in whorls of three and rarely opposite each other.

Form and size: The catalpa has a short, thick and twisted trunk with an

irregular head.

Range: Central and eastern United States.

[Illustration: FIG. 84.--Hardy Catalpa Trees.]

[Illustration: FIG. 85.--Bark of the Flowering Dogwood.]

Soil and location: It grows naturally on low bottom-lands but will also

do well in poor, dry soils.

Enemies: Practically free from disease and insects.

Value for planting: The catalpa grows very rapidly and is cultivated in

parks for ornament and in groves for commercial purposes. The _hardy

catalpa_ is preferable to the _common catalpa_ for planting.

Commercial value: The wood is extremely durable in contact with the soil

and is consequently used for posts and railroad ties.

Other characters: The _flowers_, which appear in late June and early

July, are large, white and very showy.

Other common names: _Indian bean_; _western catalpa_.

Comparisons: The _white flowering dogwood_ (_Cornus florida_) is a small

tree which also has its leaves in whorls of three or sometimes

opposite. It can be readily told from other trees, however, by the

small square plates into which the outer bark on the trunk divides

itself, see Fig. 85, and by the characteristic drooping character of

its branches. It is one of the most common plants in our eastern

deciduous forests. It is extremely beautiful both in the spring and

in the fall and is frequently planted for ornament. There are many

varieties of dogwood in common use.

WHITE MULBERRY (_Morus alba_)

A small tree recognized by its _small round reddish brown buds_ and

_light brown, finely furrowed_ (wavy looking) _bark_.

The tree, probably a native of China, is grown under cultivation in

eastern Canada and United States. It grows rapidly in moist soil and is

not fastidious in its light requirements. Its chief value is for

screening and for underplanting in woodlands.

The _red mulberry_ (_Morus rubra_) is apt to be confused with the white

mulberry, but differs in the following characters: The leaves of the red

mulberry are rough on the upper side and downy on the under side,

whereas the leaves of the white mulberry are smooth and shiny. The buds

in the red are larger and more shiny than those of the white.

The _Osage orange_ (_Toxylon pomiferum_) is similar to the mulberry in

the light, golden color of its bark, but differs from it in possessing

conspicuous spines along the twigs and branches and a more ridged bark.

Studies of Trees · 第 3 / 9 章