Control of Lepidopterous Larvae, 1987:

‘Early Round Dutch’ variety cabbage was direct seeded in single-row beds with 40-inch centers in a Willacy fine sandy loam soil at the Texas Agricultural Experiment Station, Weslaco, Tex. Plots measured 55 ft by 2 rows and were bordered by 1 row of grain sorghum. Treatments were replicated 5 times in randomized complete block design. Spray applications were applied by tractor-mounted CO2-powered boom calibrated to deliver 20 gal/acre at 60 psi operated at 3 mph. Following the initial spray treatments on 17 Nov, all treatments had 5 plants/plot sampled weekly for larvae. Treatments that had populations exceeding a mean of 0.3 larvae/plant were sprayed the following day. On 12 Jan 1988 10 cabbage heads were randomly selected from each plot and rated for marketability. A head was considered marketable if no visible evidence of larval feeding damage was observed on the head or wrapper leaves.