The selective use of pesticides on cereal crop margins for game and wildlife: the British experience.
A system of cereal crop margin management is described whereby pesticide use was modified over the outer 6 meters of the crop. This work represents the results of six years' research conducted in the United Kingdom. Pesticide use was modified by either using selective compounds in preference to the usual broad-spectrum, or residual pesticides or by the exclusion of certain compounds with proven adverse side effects aganist non-pest, non-target species. These field margins, known as "conservation headlands" permitted the survival of certain broadleaved weed species and their associated insect faunas in the crop edges and are of proven benefit to gamebirds, butterflies, other beneficial insects and declining rare arable weeds. The agronomic consequences and costs of implementing such a management programme may include effects on grain yield, quality, moisture content, weed seed contamination and harvesting. Experimental evidence for the size of these effects is presented here and used as the basis for a preliminary analysis of the potential costs of these techniques under U.K. conditions.