× Aesculus Bushii Schn., probably a hybrid of Aesculus discolor var. mollis Sarg. and Aesculus glabra var. leucodermis Sarg., has been found in the neighborhood of Fulton, Hempstead County, Arkansas; and what is evidently a hybrid of Aesculus discolor var. mollis and the typical form of Aesculus glabra occurs near Starkville, Oktibbeha County, Mississippi.
× Aesculus mississippiensis Sarg., a probable hybrid between Aesculus glabra and Aesculus Pavia with characters intermediate between those of its supposed parents, occurs near Brookville, Noxubee County, Mississippi. The mingling of a species of the Octandræ and of the Eupaviæ in these hybrids of Aesculus is shown by the presence of both hairs and glands on the margins of the petals.
2. [Aesculus octandra] Marsh. Sweet Buckeye.
Leaves with slender or slightly pubescent petioles 4′—6′ long, and 5—7 elliptic or obovate-oblong leaflets, acuminate and usually abruptly long-pointed at apex, gradually narrowed and cuneate at base, sharply and equally serrate, glabrous above except on the midrib and veins sometimes clothed with reddish brown pubescence, when they unfold more or less canescent-pubescent on the lower surface, becoming glabrous at maturity, with the exception of a few pale or rufous hairs along the stout midrib and in the axils of the principal veins, dark yellow-green, duller on the lower than on the upper surface, 4′—6′ long, and 1½′—2½′ wide; petiolules 1/12′—½′ in length; turning yellow in the autumn before falling. Flowers opening in early spring when the leaves are about half grown, 1′—1½′ long, pale or dark yellow, rarely red, pink or cream-colored (var. virginica Sarg.), on short glandular-villose pedicels mostly unilateral on the branches of the pubescent clusters 5′—7′ in length; calyx campanulate, glandular-villose; petals connivent, very unequal, puberulent, the claws villose within, limb of the superior pair spatulate, minute, the long claws exceeding the lobes of the calyx, those of the lateral pair obovate or nearly round and subcordate at base; stamens usually 7, rather shorter than the petals, with straight or inclining subulate villose filaments; ovary pubescent. Fruit 2′—3′ long, generally 2-seeded, with thin smooth or slightly pitted pale brown valves; seeds 1½′ to nearly 2′ wide.
A tree, sometimes 90° high, with a tall straight trunk 2½°—3° in diameter, small rather pendulous branches, and glabrous or nearly glabrous branchlets orange-brown when they first appear, becoming in their second year pale brown and marked by numerous irregularly developed lenticels. Winter-buds ⅔′ long, rather obtuse, with broad-ovate pale brown outer scales rounded on the back, minutely apiculate, ciliate, and slightly covered with a glaucous bloom, the inner scales becoming sometimes 2′ long, bright yellow or occasionally scarlet. Bark of the trunk about ¾′ thick, dark brown, divided by shallow fissures and separating on the surface into small thin scales. Wood light, soft, close-grained, difficult to split, creamy white, with thick hardly distinguishable sapwood; used in the manufacture of artificial limbs, for wooden ware, wooden hats, paper pulp, and occasionally sawed into lumber.
Distribution. Rich river-bottoms and mountain slopes; southwestern Pennsylvania (Alleghany, Greene and Fayette Counties), southward along the mountains to east Tennessee, and northwestern Georgia, and westward to north central Ohio (near Plymouth, Richard County), southeastern and southern Indiana (near Aurora, Dearborn County, and on the banks of Dry River near Leavenworth, Crawford County, C. C. Deam) and to southern Illinois (near Golconda, Pope County, shrub 6′—12′ high, E. J. Palmer); the var. virginica at White Sulphur Springs, West Virginia.
Occasionally cultivated in the parks of the eastern United States and Europe.
× Aesculus hybrida DC., with red and yellow flowers, believed to be a hybrid of Aesculus octandra and Aesculus Pavia, appeared in the Botanic Garden at Montpelier in France early in the nineteenth century, and in many varieties is cultivated in Europe and occasionally in the eastern United States.