Downy brome (Bromus tectorum. L.), a serious grass weed in eastern Oregon can be partially controlled in wheat by metribuzin [4-amino-6-tertbutyl- 3-(methylthio)-as triazin -5(4H)-one]. However, cultivars of many crops Lave been reported to differ in their level of tolerance to metribuzin. This lack of tolerance has led to the investigation...