Weed Control in a Fruit Tree Nursery with Herbicide-Impregnated String1

Abstract

Abstract String impregnated with simazine, atrazine, and diuron (6.6%, 2.2%, and 2.2% by weight) controlled weeds in rows of 8 month-old peach (Prunus persica (L.) Batsch) and apricot (P. armeniaca L.) seedling nursery stock. A single strand of herbicide-impregnated string controlled all weed growth in a band 30.5 cm wide when placed at the base of the seedlings on the surface of a Fox sandy loam soil. Complete weed control was obtained from the fall of 1973 to the fall of 1974. Placement of the string at various heights above the soil surface gave less satisfactory weed control than surface placement, permitted less release of herbicide and caused injury to young leaves which came in constant contact with the string. A wheat bioassay of the nursery soil after seedling removal indicated no phytotoxic residues. Chemical analysis of the string at the end of the experiment showed that 88% of the herbicide was released when one strand of string was placed on the soil surface. This resulted in a concentration of 4.05, 1.35 and 1.35 kg/ha of simazine, atrazine and diuron, respectively, in the treated area. No phytotoxicity from the soil surface string placement was observed on peach or apricot nursery trees.