Miller, Jeffrey C.; West, Kenneth J. 1987. Efficacy of Bacillus thuringiensis and diflubenzuron on Douglas-fir and oak for gypsy moth control in Oregon. Journal of Arboriculture. 13(10): 240-242.
The insecticides Bacillus thuringiensis (Bt) anddiflubenzuron (DFB) were tested for the effect of killing se-cond instar gypsy moth larvae on foliage of Douglas-fir andOregon white oak. Larval mortality differed significantly bet-ween the insecticides and check treatments. No significant dif-ferences in larval mortality were observed after one treatmentof Bt or DFB, or after two treatments of Bt. No significant dif-ferences were noted between larval mortality on the foliage ofeither host plant. Effects of the insecticides were apparent 64days post-application for all treatments.