Eastern Tent Caterpillar Control on Choke Cherry, 1981

A field of choke cherry in the Rose Lake Wildlife Research Area, Clinton Co., Ml was selected for evaluation of insecticides. Five materials were tested. Egg masses and small tents from neighboring areas were transferred to selected trees (1.5 to 4.5 m high) in the study area. Larvae were allowed to develop for approximately 3 weeks after transfer. The trees were treated on May 19 when the tents had enlarged to approximately 20 to 40 cm in diameter and the maj’ority of larvae were 3rd and 4th instars. The number of larvae per tent were counted prior to treatment. Insecticides were applied with a trombone sprayer and trees were sprayed to the run off point. The number of tents sprayed varied from 5 to 8 depending on the treatment. Skies were sunny at treatment time with an air temperature of 18°C and a light breeze of 5-10 mph. Mortality evaluations were made 7, 10 and 13 days after treatment by counting the number of dead larvae in each tent. Data were analyzed using AN0VA techniques. An arcsine percent transformation was performed on the percentage data.