Abstract
The methyl ester of diclofop {2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid} applied at 0.8 to 1.4 kg ai/ha and incorporated prior to seeding winter wheat (Triticum aestivum L.) controlled downy brome (Bromus tectorum L. ♯ BROTE) better than when applied preemergence at 1.7 kg/ha in 2 of 4 yr. The emulsifiable concentrate and a granular formulation of diclofop performed similarly. Controlling downy brome improved wheat yields 3 of 4 yr. However, preplant-incorporated applications of diclofop at 1.4 kg/ha reduced wheat yield 1 of 4 yr. Greenhouse data indicated that diclofop dissipated more rapidly in moist soil than in air-dry soil.