Identifying and Controlling Pigweed in a New Ryegrass Lawn

A Southern California lawn has crabgrass and a round, non-flowering weed called "pigweed" by a neighbor. The expert identifies it as likely Prostrate Pigweed (Amaranthus blitoides), native to western North America. Most pigweeds are chemically sensitive, so control is easy. Suggests a web search for Amaranthus or a Missouri Extension site for ID help.