Control on Salad Crops, 1988:

Abstract

Abstract The first crop of lettuce was direct-seeded at the Muck Crops Branch, Willard, Ohio, on 17 May. Cultivars planted were ‘Summer Bibb’ (Boston bibb), ‘Valmain’ (romaine), ‘Slobolt’ (green leaf), ‘Salad king’ (endive), and ‘Florida Deep Heart’ (escarole). Plots were 3 rows wide on 16-inch centers, 18 ft long, and separated by 4-ft alleys. Each treatment on each cultivar was replicated 4 times in a randomized complete block design. All plots were treated on 24 Jun with Sevin 80 S, 0.4 lb (AI)/acre, to encourage aphid infestation. Treatments were applied 8-9 Jul with a boom sprayer delivering 50 psi and 50 gal/acre. Weather immediately following treatment was very hot, with daytime highs near 100°F. On 12-14 Jul aphids were counted on 3 plants in each plot by visual inspection of one-half (escarole and bibb) or one-quarter (endive, romaine, and green leaf) of the leaves on each plant. Red lettuce, ‘Red sails,’ was direct seeded at the Muck Crops Branch on 7 Sep. Plot arrangement and experimental design were identical to the earlier planting, but no initial application of Sevin was made. Treatments were applied on 26 Sep, and weather immediately following treatment was cool. On 30 Sep, aphids were counted on 5 plants in each plot by visual inspection of all leaves on the plant.