Field experiments were conducted in 1986 and 1987 to determine the effect of herbicide rate, growth stage at time of application, and addition of adjuvant on pitted morningglory control and cotton injury by fluometuron and methazole. Fluometuron and methazole were applied as over-the-top postemergence treatments to cotton at the cotyledon and 2-leaf growth stages. Fluoseturon rates were 0.56, 0.84, and 1.12 kg/ha and methazole rates were 0.28, 0.56, and 0.84 kg/ha. All herbicide rate by growth stage combinations were applied alone, with a surfactant (0.6% v/v), and with DSMA (2.24 kg/ ha). All treatments followed an application of pendimethalin (1.12 kg/ha). All treatments were followed by a directed application of prometryn (0.56 kg/ha) + MSMA (2.24 kg/ha) and a layby treatment of linuron (1.12 kg/ ha). The carrier rate for all treatments was 93 1/ha. The experimental design was a randomized complete block with three replications.

Pitted morningglory control was better for most herbicide-adjuvant combinations when applied at the cotyledon growth stage. Pitted morningglory control was usually not increased by the addition of DSMA compared to no additive, while the addition of a surfactant increased pitted morningglory control for some treatments. Pitted morningglory control was not significantly different due to fluometuron rate, while crop injury was greater for higher rates of methazole and fluometuron.