Axyris amaranthoides L.
Family: Amaranthaceae
Russian-Pigweed
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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.

Erect, 2-8 dm, with numerous short, ascending branches; lvs short- petioled, lanceolate, stellate-hairy beneath, to 8 cm, progressively reduced above; pistillate panicles commonly on long, naked peduncles; bracts of the pistillate fls in 3's, the middle one the largest; pistillate cal 2 mm, stellate-hairy; staminate spikes 2-10 mm, the fls minute; fr brown, 2-3 mm; 2n=18. Native of Siberia, becoming a weed in our range, especially northward.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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