Uncropped edges of arable fields managed for biodiversity do not increase weed occurrence in adjacent crops

Ten experimental management regimes, designed to quantify benefits to weed control and wildlife conservation on uncropped held edges of expanded width , were examined for effects on the weed flora within adjacent arable crops. The treatments involved cutting, sowing and herbicide regimes, with differ ing effects on plant and invertebrate populations. The relative abundance o f all plant species within the adjacent crop edge was monitored using perma nent quadrats between 1987 and 1991. The field edge management regimes affe cted neither the total relative plant abundance, nor the relative abundance of most common species, within the adjacent crop edge. While frequencies o f Avena spp were initially greatest adjacent to margins cut in spring and a utumn, this effect was lost through time, and the greater abundance of Phle um pratense and Leucanthemum vulgare adjacent to the field edges in which t hey had been sown presented no threat to good husbandry. The management of uncropped arable field edges to enhance biodiversity is very unlikely to af fect weed levels within the crop, especially where they contain, or are sow n with, non-invasive perennial species. (C) 1999 Elsevier Science Ltd. All rights reserved.