Reldan Insecticide Field-Tested on Western Spruce Budworm, Payette National Forest, Idaho, 1977

摘要

Reldan (chlorpyrifos-methyl) was field tested against western spruce budworm (Choristoneura occidentalis) on grand fir (Abies grandis) on the Payette National Forest, Idaho, in June and July 1977. The insecticide was applied by helicopter at dosages of 8, 4, and 2 oz a.i./gal/acre (0.56, 0.28, and 0.14 kg a.i./1/ha). Population reduction of 90.2, 88.3, and 63.4 percent mortality (check mortality 30 percent) at 15 days after treatment were obtained. At the dosage rates tested, Reldan killed fewer budworms but showed higher variability within treatments and less foliage protection than did Orthene and Sevin-4-oil, two other insecticides currently registered for use against western spruce budworm. Further testing of Reldan is not recommended.