1. Axyris amaranthoides Linnaeus, 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.
Flowering summer-fall. Waste places; 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.