Part 8

General: Bark thin, pale yellow-green to silvery gray when young, eventually becoming dark brown or gray and rough. A small to medium-sized tree, of rapid growth but short-lived. Often one of the first forest trees to become established on recently burned areas; the most widely distributed tree of North America. Most common in northern Pennsylvania. Wood used chiefly for paper pulp.

Leaves: Simple, alternate, 3″-4″ long, dark green above, paler below, margins with coarse teeth; leaf-stems flattened; silvery when unfolding in spring.

Twigs: Rather stout, brownish gray, sometimes with a coating of pale, wooly down. Buds blunt-pointed, dull, seldom curved, often wooly.

Fruit: Similar to quaking aspen. Flowers, in the form of hanging catkins, appear before the leaves in the spring, as is the case with quaking aspen.

General: Bark similar to that of quaking aspen, but usually darker. A small to medium-sized tree; short-lived. Most common in southern Pennsylvania. Wood used chiefly for paper pulp.

Leaves: Simple, alternate, long and narrow, short-stemmed, sharp pointed, fine teeth on the margin, average length 3″; dark green above, much lighter below. The stipules (“small leaves” at the base of leaf-stems of the main leaves) remain through most of the summer.

Twigs: Slender, brittle at the base, bright reddish brown to orange-green. Buds covered by a single scale, small, cone-shaped, sharp-pointed.

Fruit: Small brown capsule, ¼″ long, borne in long hanging clusters; ripens in May or June. Each tiny seed surrounded by tufts of long silky hair.

General: Bark thick, dark brown, separating into broad, flat plates or ridges as the tree grows older. A small to medium-sized tree. Only native willow which grows to a fair size. Found mainly in moist situations. Often several trunks arise from the same root system. Weeping willow (S. babylonica) and brittle willow (S. fragilis) are introduced trees often planted for ornamental purposes.

Leaves: Simple, alternate, narrow, with tapering tip, shiny above, paler below and usually with reddish brown hairs near the base; 2″-5″ long, margins with short incurved teeth.

Twigs: Smooth, reddish brown, often covered with a thin gray coating which peels or rubs off easily; bitter when chewed; with minute, rounded gray lenticels. Buds smooth, shiny, sharp-pointed, same color as twigs but often tinged with green.

Fruit: Round, black with a purplish tint, ⅓″-½″ in diameter, containing a single round, stony seed. Arranged in hanging clusters. Flowers white, in 4″-long upright clusters in June.

General: Bark on young trunks smooth, dark red-brown, marked with numerous raised horizontal lines (lenticels), somewhat resembling that of sweet birch; later breaking into thick irregular plates with upturned edges. A large tree in the northern part of the State; medium-sized in the southern counties. Wood used chiefly for quality furniture and interior finish.

Leaves: Simple, alternate, 2″-4″ long, entire or wavy margin; dark green and shiny above, often downy on the underside; turning a vivid red in early autumn.

Twigs: Smooth, grayish to reddish brown; the white pith separated by dark lines. Buds rounded in cross section, pointed, reddish brown, ¼″ long.

Fruit: Cherry-like, ⅓″-⅔″ long, dark blue, 1-seeded, with thin flesh; borne singly or in 2’s or 3’s in a cluster; ripens in autumn.

General: Bark on young trees smooth or scaly, light gray; on older trunks dark gray, broken into blocks and resembling alligator hide. A medium-sized tree, often flat-topped, with horizontal branches and short spur-like twigs. Grows mainly on swampy lands, but found elsewhere. Wood very difficult to split; used chiefly for boxes, fuel and railroad ties.

Leaves: Simple, alternate, 3-5 lobed, 4″-7″ across, generally wider than long; light green above, paler and wooly beneath. Base of leaf-stem hollow, enclosing next year’s bud.

Twigs: At first green and hairy, later brownish, smooth; zigzag. Buds cone-like with a single smooth, reddish brown scale.

Fruit: A round “button-ball,” single or occasionally in 2’s on a tough slender stalk. These fruit clusters are light brown, 1″-1¼″ in diameter, consist of many seeds, each surrounded at the base by silky hairs; usually hang throughout the winter.

General: Bark of two layers, the outer peeling in brown flakes, the inner whitish, yellowish or greenish; on base of old trunks dark brown and fissured. A tree of large size; mature trees often very massive. Prefers stream banks. Wood used for furniture, crates, butcher blocks, and flooring. Also known as American sycamore. The London planetree (P. acerifolia), with 2, sometimes 3, “button-balls” on a stalk, is more commonly planted as a shade tree.

Leaves: Palmately compound, opposite; usually with 7 leaflets, each 4″-9″ long, wedge-shaped, long-pointed, smooth when full-grown; turning a rusty yellow in autumn.

Twigs: Stout, usually not hairy. Buds blackish brown, sticky, large; end bud ½″-1″ long.

Fruit: Roundish capsule, 1½″-2½″ in diameter, green husk with prickles; breaks into three parts when ripe releasing 1 or 2 large, shiny brown, non-edible seeds. Flower ¾″ long; showy-white and spotted with yellow and red. Flower clusters erect, 8″-12″ long.

General: Bark grayish, broken into thin plates. A medium to large-sized tree. Introduced from Europe and is a common shade tree in the State. Leaves are often browned by diseases. Also known as European buckeye. Two rather similar trees are native to southern Pennsylvania—Ohio buckeye (A. glabra) and yellow buckeye (A. octandra).

Leaves: Simple, alternate, somewhat heart-shaped, 4″-7″ long, shiny dark green on top, smooth beneath except for tufts of rusty hair; sharply toothed on margin.

Twigs: Green or reddish when young, turning brownish red; usually zigzag. Buds deep red to greenish, usually lopsided, with 2-3 visible scales.

Fruit: Nutlike, thick-shelled, downy, about the size of a pea; borne in groups from a long stem attached to narrow leaflike blade or bract. The clustered fruit and bracts may remain on the tree until late winter. Flowers yellowish white, fragrant.