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|Family: Amaranthaceae||View Description||Dichotomous Key|
|Genus: Amaranthus||View Description||Dichotomous Key|
|Species:||View Description||Dichotomous Key|
Amaranthus retroflexus L.
Habit: Monoecious. Stem: erect, 15--150(200) cm, branched or not, green or red, densely to moderately woolly. Leaf: petiole 25--80 mm; blade 20--150 cm, 10--70 cm wide, ovate to rhombic-ovate, base wedge-shaped, tip obtuse to acute. Inflorescence: terminal, panicle-like, generally erect, many-branched, lateral axes short, thick, 2--5(10) cm, 1.2--2.5 cm wide (including flowers), green or silver-green; bracts (2.5)4--6(8) mm, 1.5--2(3) × > perianth, spine-like, lanceolate to awl-shaped. Flower: staminate perianth parts 4--5, 2--3 mm, +- equal, stamens (3)4--5; pistillate perianth parts 5, 2--3.2 mm, +- equal, spoon-shaped to obovate, overlapping, reflexed in age, tip rounded to +- notched, mucronate; stigmas 3, reflexed. Fruit: circumscissile; 1.7--2.5 mm, < perianth, ovoid to obovoid, lid +- wrinkled near base, gray-cream to +- brown. Seed: 1--1.3 mm, lenticular, obovate, dark-brown to black, smooth, shiny. Chromosomes: 2n=34.
Ecology: Agricultural fields, disturbed areas; Elevation: < 2400 m. Bioregional Distribution: NCo, NCoRI, GV, CW, SW, SNE; Distribution Outside California: native to central and eastern North America; cosmopolitan weed. Flowering Time: Jun--Nov
eFlora Treatment Author: Mihai Costea
Jepson Online Interchange
Previous taxon: Amaranthus powellii
Next taxon: Amaranthus spinosus
Citation for this treatment: Mihai Costea 2016. Amaranthus retroflexus, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=12941, accessed on February 13, 2016.
Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on February 13, 2016.