7. Vitis rupestris Scheele (sand grape)

V. rupestris f. dissecta (Eggert ex L.H. Bailey) Fernald

Pl. 582 a; Map 2723

Young stems circular in cross-section or somewhat angled, glabrous or sparsely and minutely hairy at flowering time, green, gray, or brown, the nodes not glaucous, not reddish-tinged. Pith interrupted at the nodes, the diaphragms 0.3–0.5 mm wide on new growth, eventually thickening to 0.5–1.0 mm wide on older branches. Older stems with the bark shredding, not appearing warty. Tendrils absent or restricted to the uppermost nodes of the main stem and branches, present at no more than 2 adjacent nodes (every third node lacking both a tendril and an inflorescence), 2- or 3-branched. Leaves with the petiole 1/2–2/3 as long as the blades, sparsely hairy to more commonly glabrous at flowering time. Leaf blades mostly 3–10 cm long, mostly wider than long, kidney-shaped to depressed-ovate in outline, often somewhat folded longitudinally at maturity, unlobed or shallowly 3-lobed, the sinuses mostly broadly U-shaped, the lobes rounded or abruptly tapered or narrowed to a sharp but broadly pointed tip, the upper surface glabrous (occasionally sparsely and minutely hairy when young), often somewhat shiny. Undersurface of young leaves glabrous or sparsely pubescent with minute, straight, more or or less spreading hairs along and/or in the axils of the main veins. Inflorescences at no more than 2 adjacent nodes, 2–7 cm long, broadly pyramid-shaped to nearly globose. Fruits mostly less than 15 per infructescence, 6–12 mm in diameter, the surface with lenticels absent, black, sometimes glaucous. Seeds 5–6 mm long, light brown. 2n=38. May–June.

Scattered in southern and central Missouri, mostly in the Ozark and Ozark Border Divisions (Pennsylvania to Virginia west to Louisiana, Texas, and Missouri). Banks of streams and rivers and bases of bluffs.

Unlike other native Missouri species of grapes, which generally climb over other vegetation and eventually up into the forest canopy, plants of V. rupestris appear to be specialized to a scrambling habit, forming low colonies on open gravel bars. Most commonly, plants are encountered without flowers and fruits, and tendrils are not very abundant on the stems, occurring infrequently toward the tips of some branches. Moore (1991) indicated that although this species is quite important in the grape-growing industry as a source of rootstocks for grafting, it has become extirpated from much of its range outside Missouri. Steyermark (1963) indicated that this attractive species should be investigated for possible horticultural use as an ornamental groundcover.