The persistence of napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] applied at 2.24- and 4.48-kg/ha was studied for 2 yr at two locations in the field. Wheat (Triticum aestivum L. ‘Arthur 71′) was severely injured when sown in the fall following a spring application of napropamide. A wheat root bioassay also showed that napropamide was persistent for more than 180 days. The yield of sweet corn (Zea mays L. var. rugosa Bonaf. ‘Gold Cup’) was not significantly reduced when grown 1 yr after the initial application of napropamide.
