Abstract Lockett 4789-A was planted on May 24'76 at the South Central Research Station, Chickasha, Oklahoma at 20 lb per acre. Eight-row plots, 200 ft long, replicated in a complete randomized block design were used. Spray applications were made with a John Deere Hi-Cycle 600 sprayer traveling at a speed of 4.5 mph at 40 psi. Insecticide applications consisted of 4 gal and 3 pints of total spray mixture per acre, with one number 8 (Spraying Systems) nozzle per row. Five applications were made between July 30 and September 6. Intervals between applications ranged from 4 to 14 days. Plots were irrigated 5 times August 5, 11, 19, 27 and Sept 8. Rainfall during the treatment period was as follows: July 30, .54”; August 4, trace; August 5, . 21”; August 6, 1.26”; August 22, .13”; August 24, trace; August 25, .73”; August 30, .17”; August 31, .07”; September 1, .47”; September 2, .03”; September 9, .70” and September 13, 2.12” for a total of 6.43”. Damage was estimated by collecting at random 100 fruits prior to spraying from the upper one-third of the plants in each plot. Heliothis sp. populations were light and boll weevil populations were moderate. On August 17, 13 larvae were collected for species determination. Fifty-four percent were H. zea and 46% were H. virescens.