Cabbage Looper Control, 1981

‘Round Dutch’ cabbage was transplanted Aug 3 in 3 ft rows (20 inch spacing between plants) at our research station near Painter, VA. Each plot consisted of a single 25 ft long row with an untreated adjacent row. Treatments were replicated 4 times and arranged in a randomized complete block design. Foliar applications were made with a propane compressed air backpack sprayer using 3 hollow cone nozzles/row. The sprayer was calibrated to deliver 50 gal water/acre (40 psi). Applications were made on Sep 6, 14, 21, 28, and Oct 7. Two Lannate treatments were applied on a weekly schedule and received sprays on Sep 6, 14, 21, 28, and Oct 5. A destructive sample was made on Oct 19; the number of loopers was recorded for 5 plants chosen from the center of each plot. Foliar injury ratings were made using a 0-5 scale as follows: 0) no damage; 1) slight feeding, less than 5% defoliation; 2) visible feeding with 5-10% defoliation; 3) moderate damage, 10-25% defoliation; 4) heavy damage, 25-50% defoliation; 5) severe damage, greater than 50% defoliation.