Field research on aldicarb management practices for upstate New York

Abstract

The need to develop aldicarb management practices in upstate New York potato fields, which would continue the benefits associated with the pesticide while protecting drinking water wells, led to a three-part research program conducted in 1983: Samples from 57 wells and three test holes were collected near potato fields in six counties; aldicarb residues were monitored in water from a tile-drained field near Willsboro; and a study of aldicarb residues in the unsaturated zone was conducted in a potato field near Phelps. Results show that aldicarb residues from applications made in June degrade with a half-life of about one month in surface soils. The persistence and transport of aldicarb residues from these later applications is shown to be less compared to the usual previous practice of applying aldicarb at planting. The potable well sampling indicates that where applications are made at the usual planting time in midspring, aldicarb residues may appear in drinking water wells located very near the treated fields. The results of this and other related studies confirm the soundness of later applications of aldicarb when the soils are warmer and when there is less soil water percolation. This practice is embodied in the current North Eastern regulations, which require application of aldicarb at plant emergence and prohibit applications within 150 m of drinking water wells.