Grain Sorghum and Soybean As Replacement Crops Following a Failed Cotton Stand

Due to recent herbicide resistance, preemergent herbicides have played a major role in cotton herbicide programs. While this greatly improves weed control in cotton, problems may arise when a cotton stand fails and a different crop must be planted into the field where the PRE herbicide was applied. The objective of the study was to determine if grain sorghum or soybean could be planted after a simulated failed cotton stand. The study used fluometuron (Cotoran 4L) and diuron (Direx 4L), two common preemergent herbicides in cotton production which both have strict plant back restrictions for grain sorghum and soybean. Previous research has been done, but lower application rates are present with fluometuron and diuron today. Grain sorghum and soybean were planted at three, six and nine week intervals after the PRE application of diuron and fluometuron. Differences had been noted in previous research between conventional deep tillage and no-till, so both were used in the study. Visual injury ratings were taken after emergence along with yield.