Amaranthus thunbergii
in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 13(2): 262. 1849.
Plants annual, pubescent when young, becoming glabrescent at maturity. Stems decumbent or erect, branched proximally, 0.7–1 m. Leaves: petiole 1/2–11/2 times as long as blade; blade obovate or obovate-elliptic to oblanceolate, 1–2 × 0.5–1 cm, base cuneate to attenuate, margins entire, apex obtuse, rounded, or slightly emarginate, mucronate. Inflorescences axillary clusters extending to near base. Bracts of pistillate flowers lanceolate, 2–4 mm, shorter than tepals. Pistillate flowers: tepals 3, reflexed, ovate-elliptic to lanceolate, 3–5 mm, apex tapering and long-aristate; style branches spreading; stigmas 2. Staminate flowers intermixed with pistillate; tepals 3, equal; stamens 3. Utricles ellipsoid or ellipsoid-ovoid, 2 mm, shorter than tepals, mostly smooth (or slightly rugose distally), dehiscence regularly circumscissile. Seeds black, subglobose or lenticular, 1–1.4 mm diam., semishiny (or minutely punctulate and reticulate).
Phenology: Flowering summer–fall.
Habitat: Uncommon, casual alien near wool-combing mills
Distribution
Introduced; S.C., native to Africa.
Discussion
Selected References
None.