Potato Pest Control with Foliar Insecticidal Sprays, 1979

'Russet Burbank' potatoes were planted 25 May, at the Rosemount Agricultural Experiment Station, 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 17 July. Insecticides were applied Jul 20, Aug 1, Aug 15, Aug 30, and Sep 14, in 100 gal water/acre at ca. 200 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. Coun Counts were made the day before and the day after spraying, except that no postspray count was made after the Jul 20 application.