COMPARATIVE EFFICACY OF OIL VERSUS WATER AS A CARRIER IN CONTROLLED-DROPLET APPLICATION, 1987: Potato seed pieces were hand-planted 12 inches apart in a Rhinebeck silt loam field on 5 Jun at the Cornell Vegetable Research Farm, Freeville, N.Y. Each plot consisted of a 33-ft row separated by 2 skipped rows. Plots were arranged in a split-plot experimental design with 4 replications. The carriers were the main plots and the insecticides were the subplots. Carriers were either water or vegetable

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... l at 2 qt/acre (Landoil—90%). Treatments were applied with a tractor-mounted controlled-droplet-applicator (CDA) sprayer delivering 5.2 gal/acre at 3500 rpm, 20 psi, and 2.3 mph. Due to the low population of CPB on 8 Jul, 100 field-collected third- and fourth-instar larvae were introduced per plot. Treatments were applied on 9 Jul and 4 Sept. Sampling methods and dates were as follows: (1) Colorado potato beetle (CPB): number of live adults and larvae/10 hills on 8, 12, 27 Jul; and CPB/6 ft on 6 and 13 Sept; (2) aphids: number of alate and apterous buckthorn, potato, and green peach aphids/5 compound leaves (from lower third of plant); and (3) potato leafhopper (PLH): number of adults and nymphs/5 D-vac sampling sites on 14, 22, and 29 Jul and 6 and 16 Sep. Weed control, fertilization, and other cultural practices were the same as those normally used in commercial production. Yields were taken on 10 Oct for the entire 33-ft row.