1. Ampelopsis arborea (L.) Koehne (pepper vine)

Pl. 579 e; Map 2710

Twigs glabrous or sparsely and inconspicuously hairy when young, becoming glabrous with age. Leaf blades 10–25 cm long, twice pinnately or pinnately then ternately compound, broadly triangular in outline, with 9–35 leaflets. Leaflets 2–6 cm long, mostly ovate, sessile or more commonly short-stalked, mostly truncate at the base, narrowed or tapered to a sharply pointed tip, the margins with a few broad coarse teeth, dark green, the upper surface shiny, glabrous or very sparsely hairy, the undersurface glabrous or sparsely hairy along the veins. Inflorescences much shorter than the leaves. Fruits 7–10 mm long, shiny at maturity, not glaucous, changing from green to pink or bluish gray and eventually to dark purple or black. 2n=40. June–August.

Scattered in southern and eastern Missouri; introduced in Boone and Jackson Counties (southeastern U.S. west to Illinois, Oklahoma, and New Mexico). Bottomland forests, swamps, and banks of streams and rivers; also wooded roadsides.