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Title: A report on the use of pesticides at two Hampshire watercress farms
Author: National Rivers Authority Southern Region
Document Type: Monograph
The watercress industry uses a variety of crop protection products to control pest and fungal problems. Malathion, a broad spectrum, contact organophosphorus insecticide is sprayed for general insect control. Dimethoate, a contact and systemic organophosphorus insecticide, controls aphids, flea beetles and midges, again by spraying. In addition, the fungicides benomyl, and mancozeb with metalaxyl, are incorporated into compost used for seedling cultivation in order to control damping off and rhizoctonia respectively. Use of pesticides is carefully regulated by the Food and Environment Protection Act (1985). Only approved compounds may be used, and then only under the conditions and for the purposes specified on the approved product label. Allowance is made, however, for use on other crops by means of an Off Label Approval (OLA) which is usually granted for a specified time period. The pesticides malathion and dimethoate, together with the three fungicides, were granted off label approval by MAFF until September 1990 subject to various restrictions. After the expiry of this approval, crops sprayed in the course of this investigation were subsequently destroyed. The watercress industry feels that continued use of these products is essential to their operation. It was agreed that a study would be carried out by the National Rivers Authority, in conjunction with Hampshire Watercress Ltd. The objective was to determine whether significant levels of malathion and dimethoate are detectable in the receiving water downstream of the cress beds after spraying, and whether the macroinvertebrate populations of the river are affected. This report details the results of the investigation.
Publisher: National Rivers Authority
Publication Date: 1991
Publication Place: Worthing
Subject Keywords: PesticidesAgricultureFarmsRegulations
Geographic Keywords: Hampshire
Extent: 49
Total file downloads: 284

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