Potato Pest Control with Foliar Insecticidal Sprays, 1978

‘Russet Burbank’ potatoes were planted May 24, at Rosemount, Mn. Treatments were applied to 4-row plots, 45-ft long, with 40-inch row spacing, randomized in complete blocks with 3 replications. Two untreated rows separated each plot. Chlorothalonil fungicide was applied weekly per label recommendations from Jun 27. Insecticides were applied Jul 18, Aug 1, 16, and 29, and Sep 15, in 100 gal water/acre at ca. 300 psi. A tractor-drawn boom sprayer with 3 drop nozzles/row was used. Potato leafhopper nymphs, green peach aphid and potato aphid apterae were counted from 35 mid-plant leaves from the center 2 rows of each plot. Counts were made the day before and the day after spraying, except applications intended for Aug 15 were delayed until Aug 16, and for Sep 12 until Sep 15.