Cabbage Loopers and Imported Cabbageworms; Feeding Damage and Control on Cabbage in Western North Carolina1

Abstract

Several tests with insecticides were performed between 1959 and 1963 to determine effective control of the cabbage looper, Trichoplusia ni (Hubner), and other cabbage caterpillars in western North Carolina. Scheduled applications of long- and short-residual registered insecticides showed best protection against feeding damage when pre-head applications of endrin dust or spray, or a dust mixture of 20% toxaphene and 2% parathion were followed by post-head applications of naled or mevinphos; however, in 1963 endrin gave inadequate control. Naled and mevinphos were generally unreliable when used exclusively from transplant to harvest. Attempts to improve residual effectiveness of these 2 materials with various adjuvants were unsuccessful. Bacillus thuringiensis Berliner gave good protection in some tests, but control was erratic. Evaluations were made of various unregistered insecticides. Two years' testing showed Bayer 44646 (4-dimethylamino- m-tolyl methylcarbamate) and Zectran® (4-dimethylamino- 3,5-xylyl methycarbamatc) gave good control of the cabbage looper and protection against feeding damage. American Cyanamid 47031 (cyclic ethylene (diethoxyphosphinyl) dithioimidocarbonate), Monsanto CP-40294 ( O-p- nitrophenyl O -phenyl methylphosphonothioatc), and Monsanto CP-40273 ( O-p -nitrophenyl O -propyl methylphosphonothioate), showed promise in 1963.