Page:TheTreesOfGreatBritainAndIreland vol04B.djvu/286

A form is known with very small fruit, var. microcarpa, Gray.’ In regard to the leaf, two varieties have been described,’ viz.:—

Var. acuminata, Wesmael. Leaflets dark green above, very white and almost glabrous beneath, nearly entire in margin. This form is more common in the southern states.

Var. juglandifolia, Rehder. Leaflets usually broader than in the preceding variety, more or less pubescent beneath, coarsely serrate at least above the middle. This is the northern form of the species.

These two varieties occur in cultivation in England, the leaves of both remaining unchanged in colour until they fall in autumn. A form of var. acuminata occurs, in which the leaflets are narrow at the base, and turn reddish brown before they fall.

There is also said to exist a horticultural variety, var. a/60-marginata, in which the leaflets are edged with white.

As Fraxinus americana may be a valuable tree for economic planting in England, its correct identification is important. Reputed trees of /. americana growing slowly usually turn out on examination to be F. vridis or some other species. In summer, the leaflets white beneath and distinctly stalked, the rachis terete and practically not grooved, and the glabrous branchlets, will readily distinguish ©, americana. The only species which closely agrees with it, F. ¢exenszs, has, when adult, fewer, usually five (rarely seven) leaflets, which are smaller and quite different in shape, being broadly oval with a rounded or acute apex. (A.H.)

The white ash is one of the best known and most highly valued trees in New England and Canada; where it occurs according to Sargent, from Nova Scotia and New Brunswick through Ontario to northern Minnesota, southward to northern Florida, and westward to Kansas, Indian Territory, and eastern Nebraska, and the valley of the Trinity River, Texas; being less common and smaller west of the Mississippi. It attains in the forest a height of 120 feet with a diameter of 4 feet and upwards, and thrives best in a deep loamy soil near the banks of streams, just as the common ash does in England. When standing alone it assumes a spreading habit with large branches.

Ridgway measured a sound tree in Wabash County, Illinois, which was 144 feet high with a clean stem 83 feet long and 9 feet in girth at the top, and 13 feet at the base, which, according to English measure, would have contained over 500 cubic feet; and Dr. C. Schneck measured a tree in the same county 144 feet high with a stem go feet long and 174 in girth above the swell at the base ; and this tree, if it carried its girth up, might have contained 1000 feet of timber.

1 This variety is common in the Gulf States, the fruit being less than ½ inch long ; whereas it usually attains 1½ to 2 inches. Sargent, however, states that both large and small fruit may occur on the same individual, and even on the same branch.

2 Cf. Rehder in Cycl. Amer. Horticulture, 607 (1900).