Control of the Walnut Husk Fly, Rhagoletis completa Cresson, with Systemic Insecticides

Abstract

Field experiments in 1964 and 1965 demonstrated the effectiveness of phosphamidon, dimethoate, and Bidrin® (3-hydroxy-N, N-dimethy-cis-crotanamide dimethyl phosphate) against the larvae of the walnut husk fly. These materials prevented shell staining when applied as sprays to nuts containing eggs or newly hatched larvae. Oxydemetonmethyl and Niagara 10242, (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) were not effective at the dosages tested. Phosphamidon applied late in the season to heavily infested trees reduced both the incidence and extent of shell staining and the incidence of moldy nut meats. The use of systemic insecticides for walnut husk fly control should make possible a reduction in the number of treatments from that currently required with contact materials.