Apple, Pre-Bloom Aphid Treatments, 1980

Test materials were applied to 5 year old Red Delicious apple trees using a Bean 35 gallon per minute hydraulic sprayer operating at 300 psi. Single tree plots were used and replicated 5 times in a randomized complete block design. Oil sprays were applied at delayed dormant stage, Apr 10, and other materials were applied at the pink stage of bud development, Apr 22. Spray materials used throughout the season include Polyram, benomyl, captan, Dithane, Thylate, azinphosmethyl, phosalone, and Karathane. Rosy apple aphid populations were evaluated on May 29 by counting all colonies visible on each tree.