Sp. Pl. 2: 979. 1753.
Stems (5–) 30–90 cm. Leaf-blades pale green, (1–) 1.5–3 × 5–9 (–10) cm. Flowers: perianth segments 3-parted, oblong to oval, apex obtuse, whitish-pubescent, with both stellate and simple trichomes adaxially; staminate whitish, less than 2 mm, stamens 3; pistillate green. Utricles red or dark-brown, heteromorphic, obovate or oval, 2.5–3 mm, with distal 2-lobed appendage. 2n = 18.
Phenology: Flowering summer–fall.
Habitat: Waste places
Elevation: 0-300 m
Introduced; Alta., B.C., Man., N.B., N.S., Ont., Que., Sask., Maine, Mass., Minn., Mo., Mont., N.H., N.Y., N.Dak., Eurasia
Axyris amaranthoides is an invasive and problematic weed, especially in crops of cereal grains. It also has been reported from Colorado and Iowa and is to be expected elsewhere.