The currently accepted scientific name of rough pigweed is Amaranthus retroflexus L. [11,14,18,20]. It is a member of the pigweed family (Amaranthaceae). There are no recognized subspecies, varieties, or forms.
Walsh, Roberta A. 1993. Amaranthus retroflexus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/