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Pigweed Amaranthus retroflexus


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credit: Lynk media/CCSA

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Alternate name: Green Amaranth, Red-root Amaranth

Family: Amaranthaceae, Amaranth view all from this family

Description Monoecious annual, upright herb with a rough, hairy stem, stout, bristly whitish-green flowering spikes, pinkish-reddish tap root.
Flowers: Dense green flower clusters interspersed with spiny green bracts in both terminal panicles and leaf axils.
Fruit: Tiny capsule with a top or lid that contains one tiny black seed.
Leaves: Simple, pinnately veined from 3-6" (7.5-15 cm) long, higher leaves have lance shape while lower ones are oval or diamond in shape.
Height: Generally 3-6' (1-2 m) up to maximum of 9' (almost 3 m).

Warning This plant is reported to be toxic if ingested. Sensitivity to a toxin varies with a personís age, weight, physical condition, and individual susceptibility. Children are most vulnerable because of their curiosity and small size. Toxicity can vary in a plant according to season, the plantís different parts, and its stage of growth; and plants can absorb toxic substances, such as herbicides, pesticides, and pollutants from the water, air, and soil.

Flower Late summer to early fall, approximately August to October.

Habitat Roadsides and cultivated soil.

Range Native to the tropical Americas, it has been introduced on most continents and occurs throughout much of North America excluding the Arctic but including the United States, Canada, Mexico and southward.

Discussion This weedy plant has several common names, including Red-root Amaranth, Redroot Pigweed, Red Rooted Pigweed, Rough Pigweed, Common Amaranth, and common tumble weed and is very similar to Slender Amaranth or (A. hybridus). No species or genus of Amaranthus are known to be poisonous, however, leaves do contain oxalic acid and may contain nitrates if grown in nitrate-rich soils. It is eaten as a vegetable in certain places around the world such as the India state of Kerala. It was also used for many food and medicinal purposes by various Native American groups.