Amaranthus viridis L.
Amaranthus gracilis Desf.
tropical regions of the world
This is a vigourous annual herb up to 1m high and is found in Summer.
Stems are generally rounded, may have some ridges, and glabrous (without hairs).
Leaves are mid to light green and deeply veined and up to 15cm long. Leaves have a long leaf stalk and have a broad base tapering to a pointed tip.
Mostly the inflorescence (group of flowers/fruit) is a dense spike, often with many branches. Flowers are small and green (sometimes with a reddish tinge). Flowers are generally radiating around the stem.
Fruit capsules are wrinkled, indehiscent (not opening to release seed when ripe), small and brown. The fruit contains smooth and glossy seeds.
Other plants easily confused with this plant
Other Amaranthus species may be confused with this plant.
Amaranthus viridis can be distinguished by its wrinkled fruit and its flower bracts being less than 1mm long and acute (pointed).
Sources & References
"Weeds - an illustrated botanical guide to weeds of Australia" by B. A. Auld and R. W. Medd
"Gardener's Companion to Weeds" by Suzanne Ermert and Leigh Clapp
"Plantnet FloraOnline" (2005) http://plantnet.rbgsyd.nsw.gov.au/
Prepared by Justin KY Chu, July 2005
Checked by IEWF, Oct 2005
Checked by Barbara Wiecek, Botanic Gardens Trust, Sydney, June 2006