Cabbage Looper Control on Cabbage, 1976

Golden Acre YR cabbage seed was planted August 24 in 40 inch beds with two seed rows per bed. Individual plots were two beds wide, 25 feet long and replicated three times in a randomized block design. Plots were separated from each other by an untreated guard bed. Treatments were started September 28 and were applied on a weekly schedule. Six applications were made during the growing season. All sprays were applied using a 2 gallon CO2 pressurized-type hand sprayer with a two nozzle boom, operated at 50-55 psi. Effectiveness of the different treatments was measured by counting the number of cabbage looper eggs and larvae on 10 plants from the middle two rows of each plot. Worm damage evaluation was made on 40 plants per plot on November 18. A 1 to 5 rating scale was used: 1 indicating no damage and 5 indicating heavy damage. Cabbage looper eggs and larvae were present in all plots most of the season, however, the majority of the larvae in the treated plots were 1st and 2nd instar, while many of those in the check plots were later instars. Very little damage was caused by the small loopers in the treated plots, whereas the larger ones caused heavy damage in the check plots.