Barnyardgrass (Echinochloa crus-galli) biotypes, resistant to different herbicides, have been reported. An experiment was conducted to compare the growth characteristics of various barnyardgrass biotypes, (i.e., propanil-resistant from Poinsett County, Ark., quinclorac-resistant from Louisiana., quinclorac/propanil-resistant barnyardgrass from Craighead County, Ark., and susceptible barnyardgra...