Plants to 1.5(-3) m. Leaves: petiole 1-7 cm, sometimes obscure; blade elliptic, often broadly so, to lanceolate-elliptic, to 35 × 19 cm, base cuneate, apex acuminate. Racemes dense, erect at least in flower and young fruit, 5-30 cm; peduncle to 5 cm; pedicel 6-13 mm, sometimes obscure. Flowers: sepals 5, white or greenish white, elliptic to oblong, equal to subequal, 3-4 mm; stamens 7-10, in 1 whorl; carpels 7-8, distinct. Achenes black, 4 mm, smooth to somewhat rugose; pericarp firmly adherent to seed.
Flowering summer-fall. Woods; 300 m; introduced; Wis.; Asia.
The only collections of Phytolacca acinosa we have seen from the flora are those made by Hugh H. Iltis and others at Olin Park in Madison, Wisconsin (WISC; three collections, the earliest 1971, the latest 1986, photographs 1996). The plants were reported to be scattered to abundant, with many seedlings or young plants of all sizes, and were found in deep shade in a deciduous forest where the species had persisted for about 25 years.
J. W. Nowicke (1968) referred to the one-seeded fruits of Phytolacca acinosa as drupelets.