Apple, Second Generation White Apple Leafhopper Aerial Appucation Evaluation, 1986

Ground airblast and helicopter applications of Seven XLR at 2.0 lb Al/acre were compared for eEFectiveness against WALH nymphs and adults. This test was conducted in an orchard containing 7-year-old trees with under-tree irrigation. Treatments were applied to unreplicated 1.0 acre plots on 27 Aug. The ground application was made with a Parker airblast sprayer delivering 400 gal/acre at a ground speed of 2 mph. The helicopter application was made at a speed of 35 mph, approximately 10 ft over the canopy, delivering 7 gal/acre. On the date of application, approximately 13.0% of the WALH population were adults. Adults were sampled with 12.5 x 17.8 cm sticky boards made from bright yellow poster board coated on both sides with Stickem Special Pest Glue, suspended from limbs with a wire hanger. Six traps were evenly spaced in each plot and left in place for a 24 h period to obtain adult counts. Nymphs were counted on 20 randomly selected leafhopper-injured leaves on terminal growth from 6 trees in each plot (120 leaves per treatment). Half of these leaves were chosen from outer canopy of the tree, the other half from lower central growth.