Search

Waterhemp’s rise to the Cornbelt’s worst weed is one of the Cornbelt’s more fascinating weed-related events over the past 40 years.  Waterhemp (Amaranthus tuberculatus) is native to the United States but is a relative newcomer to crop fields. Prior to waterhemp’s ascent, redroot pigweed (A. retroflexus) and smooth pigweed (A. hybridus) were the pigweed species most commonly found in crop fields. Pammel (1913) described redroot pigweed as abundant in every Iowa county, whereas he stated waterhemp (A.