Germination of Winter Annual Species from a Rangeland Community Treated by Paraquat

Abstract

Three annual plant species — erect plantain (Plantago erectaMorris), common chickweed [Stellaria media(L.) Cyrill.], and silver hairgrass (Aira caryophylleaL.)—are commonly found and may dominate a unique flora on areas sprayed with paraquat (1,1′-dimethyl-4,4′-bipyridinium ion) in cismontane rangelands of California. The basis of this phenomenon is shown to be temperature-related germination requirements, novel seed characteristics, and lack of competition.