Amaranthus retroflexus L.
rough pigweed (redroot amaranth)
Amaranthaceae (Amaranth family)

Introduction to Vascular Plants


© Bryan Kelly-McArthur     (Photo ID #85743)


E-Flora BC Static Map

Distribution of Amaranthus retroflexus
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Species Information

Annual herb; stems 50-100 cm tall, simple to freely branched, long-hairy with dandruff-like scales below the flowers.
Alternate or opposite, leaf blades 3-8 cm long, hairy below, at least along the veins, narrowed abruptly to the stalks.
Inflorescence in terminal and axillary spikes; bracts long and needle-shaped or spiny; stamens usually 5, sometimes 4.
Capsules opening along an "equator", the top coming off like a lid, 1-seeded; seeds 1 mm long, rounded and convex.

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Habitat and Range

Moist to dry fields, disturbed areas and waste places in the lowland, steppe and montane zones; frequent in S BC, rare northward; throughout N. America and the Old World.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Amaranthus retroflexus var. salicifolius I.M. Johnst.