Potato Insect Control, 1994

Potatoes were planted on 30 Apr in South Deerfield, Massachusetts. Fertilizer (600 lbs 10N:10P:10K/acre) was banded into the furrow at planting. Soil type was a fine sandy loam with a pH of 5.6. Manzate (fungicide) was applied at 1 lb. Al/acre on 30 Jun and 25 Jul. Treatments were replicated 4 times in a randomized complete block design. Each plot consisted of two 30 ft. rows with a 6 ft. fallow area separating each plot. All samples were taken from the center plants in each plot. Treatments were applied with CO2-pressurized sprayers at 40 psi, delivering about 70 gal/acre. CPB population densities were determined by counting larvae on 5 whole plants or stalks in each plot. The number of early instars (first and second) or late instars (third and fourth) were recorded. All treatments were first applied on 15 Jun, and again on 22, 29 Jun, 6, 13, 20 and 27 Jul.