Pecan, Walnut Caterpillar Control, 1978

Infested trees in a pecan orchard located 2 miles west of Stillwater, Oklahoma, were treated on Jun 29. Application equipment consisted of a John Bean 55 sprayer, series L-155 and a 785 John Bean Spraymasterdeluxe gun which delivered 1.76 gal/min of finish spray at 300 psi. Infested areas of trees were sprayed until runoff. Treatments were randomized and replicated four times. Temperature at time of application was 85°F and the wind velocity was 0 to 5 mph. Pretreatment and posttreatment counts were determined by examining the foliage of an area of the tree that had been found to be infested. Larval populations were estimated at these locations for pretreatment and posttreatment counts. Larval size at time of treatment ranged from one-half to three-fourths inch in length.