The great herbicidal developments of recent years give hope for chemical control of annual bluegrass, Poa annua, which is a major weed problem in bentgrass turf. Annual bluegrass produces an abundance of seed and quickly dominates bentgrass turf that is not growing at its optimum. Annual bluegrass might be controlled by prevention of seed set, pre-emergence control, and plant eradication. The original purpose of this study was to evaluate chemicals which offered promise of annual bluegrass control by checking seed set. However, necessity led to consideration of any promising chemical regardless of its method of control.