Published online by Cambridge University Press: 12 June 2017
Field experiments were conducted in 1982 and 1983 in cotton (Gossypium hirsutum L.) to evaluate alternatives in grass weed management programs with the use of postemergence herbicides and to assess the economic potential for incorporating the new over-the-top grass weed herbicides into total cotton production practices. Twelve weed management systems using the grass herbicides sethoxydim {2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one} and fluazifop {(±)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid} were compared to six standard systems. Differences in cotton production costs among the 18 systems were due to cost differences in total weed management. Equal or greater net return values were obtained when over-the-top herbicides followed fluometuron {N,N-dimethyl-N′-[3-(trifluoromethyl)phenyl)urea} preemergence or when these materials were applied twice compared to the over-the-top materials used in conjunction with trifluralin [2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine] preplant incorporated or with directed postemergence materials. High net returns were the result of both high seed cotton yields and low total production costs.