Control of the Elm Leaf Beetle in Arizona

Trunk injections of 3-ml dosages of Bidrin® (3-hydroxy- N, N -dimethyl- cis -crotonamide dimethyl phosphate) spaced 6 inches apart around the circumference of Chinese elm trees, controlled Pyrrhalta luleola (Muller) for periods of 6 weeks or longer. Oxydemetonmethyl, applied at the same rate, controlled elm leaf beetles for only 4 weeks. Delaying Bidrin treatments until the foliage was severely Injured reduced the length of the control period to 4 weeks. The Bidrin treatment was less effective on water-stressed trees.