Red Pigweed

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 oblan-ceolate, 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).

Flowering summer-fall. Uncommon, casual alien near wool-combing mills; introduced; S.C.; native to Africa.

thunbergii: named after Carl Peter Thunberg (1743-1828)

Ascending or erect annual herb, up to c. 55 cm high. Stems simple or branched, angular, almost hairless below but usually with long multicellular hairs towards the top. Leaves more or less narrowly elliptic, rhomboid or spathulate, up to 4.5 × 3 cm, almost hairless or thinly hairy below; base often decurrent along the petiole. Flowers greenish in short axillary clusters, unisexual. Capsule ovoid-ellipsoid, 2.5-3.5 mm long, with a short beak.

From Ethiopia and Somalia to DRC and Angola, Botswana, Namibia and South Africa.

Amaranthus thunbergii, commonly known as Thunberg's amaranthus or Thunberg's pigweed, is found in Africa.

The leaves are used as a flavouring or leafy vegetable.