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Key to Most Important Species

A. Twigs 4-angled; flowers perfect.

(F. quadrangulata) BLUE ASH

AA. Twigs round; flowers dioecious.

B. Branchlets, petioles and leaf linings smooth.

C. Buds brown; leaflets stalked.

D. Leaves whitish beneath.

E. Wings of fruit broad; leaflets blunt.

(F. Caroliniana) SWAMP ASH

EE. Wings of fruit narrow; leaflets taper pointed.

(F. Americana) WHITE ASH

DD. Leaves green beneath. (F. lanceolata) GREEN ASH

CC. Buds black; leaflets sessile. (F. nigra) BLACK ASH

BB. Branchlets, petioles and leaf linings downy.

C. Twigs slender; keys very long and slender.

(F. Pennsylvanica) RED ASH

CC. Twigs stout; leaves pale green.

D. Trunk cylindrical. (F. Oregona) OREGON ASH

DD. Trunk bulging at base. (F. profunda) PUMPKIN ASH

Ash trees are easily distinguished in the woods by the opposite arrangement of their pinnately compound leaves. Hickories, walnuts, and other trees with similar leaves will be found to have an alternate arrangement. The snugly fitting bark, broken into small, often diamond-shaped plates, gives the trunk of an ash a trim, handsome appearance in the winter woods. The seeds winged and shaped like darts, are borne profusely, and are quite sufficient identification. No other tree bears a fruit that can be confused with this one.

There are thirty known species in the genus Fraxinus, half of which inhabit North America, covering all sections except the coldest. The Northern Hemisphere in the Old World is as well supplied. Cuba, northern Africa and the Orient have tropical species.

It is not so clear to ordinary people as it is to the botanists that the ashes belong to the olive family. If we knew all the tropical members of the group we might not be surprised. The relationship is established by morphological characters obvious only to trained observers.

The name ash is applied to several other kinds of trees. Mountain ashes belong to the rose family. Prickly ash belongs with the sumachs in the rue family. "Yellow ash" is a Tennessee name for Cladrastis lutea, the virgilia, a member of the locust family. The "hoop ash" of Vermont is the hackberry, a close relative of the elms.

White Ash (Fraxinus Americana, Linn.)--A tall, stately tree, 75 to 125 feet high, with straight, columnar trunk reaching 6 feet in diameter, and high pyramidal or round head of erect, stout branches. Bark closely furrowed into many deep, diamond-shaped ridges and hollows, dark brown or grey, thick. Wood reddish brown, with paler sap wood, tough, elastic, coarse, heavy, hard, not durable in soil, becoming brittle with age. Buds smooth, dark brown, plump, leathery, on pale twigs. Leaves, opposite, pinnate, 8 to 12 inches long, of 5 to 9 leaflets, usually 7, appearing late, falling early; autumn colour purple or yellow; leaflets stalked, smooth when mature, dark green above, pale, often silvery beneath, oblong-lanceolate, with entire or wavy margins. Flowers, May before leaves, dioecious, in panicles, at first compact, later long and loose; staminate purple, later yellow, stamens 3 on short filaments; pistillate purple, vase shaped, with elongated style and spreading, divided stigma. Fruit, September, slender, dart-like keys, 1 to 2 inches long, pointed, wing twice the length of the round, tapering body. Preferred habitat, rich, moist soil. Distribution, Newfoundland and Nova Scotia to Florida; west to Ontario, Minnesota and Texas. Uses: An admirable park and street tree. Wood used for agricultural implements, frames of vehicles, tool handles, oars, furniture, interior finish of houses, stairs, and fuel.

The white ash is one of the trees that holds its own in our Eastern forests, the peer of the loftiest oak or sycamore or black walnut. Narrow as its head is when crowded in the company of other trees, it can broaden out into a canopy of benignant shade when it has room to grow naturally. The white of its leaf linings enters into its name. The pale twigs and bark also justify its name.

The tree is a column of grey in winter, topped by upright branches and erect, rigid twigs, set with mathematical accuracy in opposite pairs. There is little grace in such a tree until June has covered it with supple new shoots, and the leaves droop and flutter in sun and wind. Then the white ash stands transformed, and all through the summer the pistillate trees are hung with bountiful clusters of pale or rosy keys that dance and gleam and fairly dazzle the eyes of the beholder.

Staminate trees ordinarily shed their flowers as soon as the bursting pollen cells have turned their purple to gold. A little mite has discovered some virtue in these flower clusters, and mite families innumerable are raised therein, causing the distorted blossoms to remain in place, though withered. I once found an old man carefully gathering these bunches in winter, thinking them to be seed of the tree. He looked incredulous when I tried to dispel his illusion, and a moment later resumed his task.