Abstract Two trials were planted in a single large field in Western N.Y. with a soil texture change between the 2 locations. Identical rates and placements of registered corn rootworm soil insecticides were used in both sites for comparison purposes. Experimental plots for the large trial, measuring 53 rows × 50 ft, and for the small trial, measuring 10 rows × 50 ft, were planted at Rich-a-Lu farm in East Aurora, N.Y., on 4 May with a 2-row corn planter at 24,000 seeds/acre. Plots were fertilized with 400 lb of 10-10-10 fertilizer banded at planting. Soils for the large trial were silt loam with 4% organic matter, and for the small trial were sandy loam. Fifty-three treatments were replicated 4 times in a complete randomized block design for the large trial, and 10 treatments were replicated 4 times in a complete randomized block design for the small trial. Supplemental nitrogen was provided with a preplant incorporated application of 40 tons manure/acre. Granular insecticides were applied at planting with Noble granular applicators mounted on the planter. Adult beetle counts averaged between 3 and 4 beetles/plant during the 1989 oviposition period throughout the entire field. Each treatment for both trials was 1 row by 50 ft. Stand counts were taken on 40 ft of row on 15 Jun. Five plants in each row were dug and the roots washed before rating root damage using the Iowa 1-6 root rating scale on 26 Jul.