ÆSCULUS GLABRA, Ohio Buckeye
- Æsculus glabra, Willdenow, Enum. Pl. Hort. Berol. 40 5 (1809); Loudon, Arb. et Frut. Brit. i, 467 (1838), Sargent, Silva N. America, ii. 55, tt. 67, 68 (1892), Man. Trees N. America, 644 (1905).
- Æsculus pallida, Willdenow, loc. cit. 406 (1809).
A tree attaining 70 feet in height and 6 feet in girth in America. Bark dark brown and scaly, becoming in old trees ¾ inch thick, ashy-grey, densely furrowed and broken into thick plates roughened on the surface by numerous small scales. Leaves with long slender stalks; leaflets five, oval or obovate-cuneate, long-acuminate, finely serrate in margin, with tufts of hairs in the bases of the serrations, glabrous underneath except for a few hairs along the midrib and tufts in the axils; petiolules short. Terminal leaflet with about fifteen pairs of nerves. Flowers in pubescent panicles, 5 to 6 inches long; calyx campanulate; petals four, pale yellow; claws shorter than the calyx; limbs twice as long as the claws, broadly ovate or oblong in the lateral pair, oblong-spathulate, much narrower and sometimes red-striped in the upper pair. Stamens usually seven, long, exserted, pubescent. Ovary pubescent. Fruit ovate or obovate, brown, 1 to 2 inches long, roughened by prickles.
The species is distinguished in summer by the glabrous leaves, which always show some cilia in the bases of the serrations. In winter the following characters of the twigs and buds may be recognised:—Twigs glabrous, shining, with orangecoloured lenticels. Leaf-scars slightly oblique on obscure leaf-cushions, crescentic or semicircular, with three groups of bundle-dots, the opposite scars wide apart and often not joined by any linear ridge. Pith large, circular, greenish. Buds not viscid; terminal much larger than the lateral, the latter arising from the twig at an angle of 45°; ovoid, acuminate; scales keeled on the back, ciliate in margin, acuminate, the pointed tips being raised outwardly, dark brown.
Var. Buckleyi, Sargent (Æsculus arguta, Buckley, Proc. Acad. Phil. 1860, p. 448), is a geographical form, occurring in Iowa, Missouri, Kansas, and Texas, and characterised by six to seven leaflets, which are sharply and unequally serrate.
No well-marked horticultural varieties are known.
The type occurs in alluvial soil in Atlantic North America, from Pennsylvania to N. Alabama, and westward to S. Iowa, Central Kansas, Indian Territory, and S. Nebraska. Sargent says that it is nowhere very common and from an ornamental point of view very inferior to Æsculus octandra.
This species was introduced, according to Loudon, in 1812, but appears to be very rare in this country. At Devonshurst, Chiswick, a tree cut down in 1905 was 60 feet in height by 6 feet in girth, but though the tree probably exists in some nurseries and old gardens, where it is mistaken for Æsculus octandra, more commonly than is supposed, we cannot mention any which are remarkable. (A.H.)
