Woglum, R.S. 1942 The commercial value during 1941-42 season of toxic oil sprays for red scale.. The Exchange: Pest Control Circular No. 90: 1-3.
Notes: Rotenone powder has given increased effectiveness to the low dosage oil sprays against black scale, but not against red scale. These experiments have demonstrated that with the addition of a purer form of rotenone, red scale control is considerably more effective.