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Redroot Amaranth (Amaranthus retroflexus)

Description

Amaranthus retroflexus is a species of flowering plant in the Amaranthaceae family with several common names, including red-root amaranth, redroot pigweed, red-rooted pigweed, common amaranth, pigweed amaranth, and common tumbleweed. Amaranthus retroflexus, true to one of its common names, forms a tumbleweed. It is native to the tropical Americas, but is widespread as an introduced species on most continents in a great number of habitats. This is an erect, annual herb reaching a maximum height near 3 m (9.8 ft). The leaves are nearly 15 cm (5.9 in) long on large individuals, the ones higher on the stem having a lance shape and those lower on the plant diamond or oval in shape. The plant is monoecious, with individuals bearing both male and female flowers. The inflorescence is a large, dense cluster of flowers interspersed with spiny green bracts. The fruit is a capsule less than 2 mm (0.079 in) long with a "lid" which opens to reveal a tiny black seed. Another of A. retroflexus's common names is pigweed because it grows where hogs are pasture-fed.

Taxonomic tree

  • Domain: Eukarya

    • Kingdom: Plantae

      • Phylum: Magnoliophyta

        • Class: Magnoliopsida

          • Order: Caryophyllales

            • Family: Amaranthaceae

              • Genus: Amaranthus