Nature Notes

BEETLE BANKS - a new phenomenon - are low ridges of earth about 4ft wide and 2ft high. They are heaped across fields by a couple of passes in each direction with the plough, and planted with various kinds of grass and flowers. Their role is to harbour predatory insects, which spend the winter in the grass, and then in spring march out into the arable crops alongside, where they devour pests such as aphids, thus reducing the amount of pesticides that the farmer needs to use.

Over the past five years research at the Game Conservancy Council's experimental farm at Loddington, in Leicestershire, has shown that ground beetles, rove beetles and spiders spread out as far as 200yds on either side of the banks, and eat a worthwhile number of pests. The thick, tussocky grass, which is never cut, has also proved congenial to partridges, which nest in it, and to harvest mice, which take up residence on the banks. This, in turn, is of benefit to kestrels, which can often be seen hunting overhead.

Planting wild flowers such as oxeye daisies and knapweed has attracted hover flies, parasitic wasps and bumblebees, all of which are beneficial. Humble artefacts though they may be, beetle banks are doing a good job.

DUFF HART-DAVIS

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