Published online by Cambridge University Press: 12 June 2017
Field experiments were conducted from 1986 to 1988 to evaluate giant foxtail control at four plant heights by six POST grass herbicides. Clethodim, fenoxaprop, fluazifop-P, haloxyfop, quizalofop, and sethoxydim controlled 95% or more of 60-cm giant foxtail all three years at the labeled herbicide application rates. Control of 7-, 15-, and 30-cm giant foxtail with fenoxaprop, fluazifop-P, quizalofop, and sethoxydim was dependent upon soil moisture conditions at application. Clethodim and haloxyfop provided the greatest control (89 to 99%) regardless of plant height or soil moisture conditions. No herbicide injured soybean. Soybean seed yield with POST grass herbicides was equal to or greater than yield in the hand-weeded plots.