Apple, First Generation White Apple Leafhopper Insecticide Evaluation, 1986

A 6-year-old orchard with under-tree irrigation was used in this test. A randomized complete block design with 4 single-tree replicates per treatment was used. Materials were applied on 16 May as dilute sprays to the point of drip with a handgun sprayer operating at 400-500 psi. Per acre rates were based on 400 gal/acre. Treatment date was determined by the first appearance of fourth instar WALH nymphs. Leafhopper populations were monitored by counting the nymphs found on 20 randomly selected leafhopper-injured leaves from each tree (80 leaves per treatment). Post-treatment mite population levels for selected treatments were determined by collecting 20 randomly selected leaves from each tree, brushing them in a mite brushing machine, and counting the mites of each species recovered.