Hedgerow management experiment relevant to agri-environment schemes: cutting regime impacts species richness of basal flora and Ellenberg indicator profiles

Hedgerow plant communities, including herbaceous species growing in the hedge base, are important conservation indicators of hedgerow habitat condition. The effects of management have the potential to alter the species richness and composition of hedgerow plant communities, but this has not previously been tested experimentally. A novel field experiment was used to test the effects of hedgerow management on hedgerow basal flora. Hedgerow cutting treatments, including relaxed cutting regimes funded under agri-environment schemes, were applied in replicated blocks at four sites in lowland UK. After 6 years of experimental cutting treatments the hedgerow plant communities were surveyed, both directly under the woody hedgerow vegetation and immediately adjacent to the hedges. For hedgerow plots cut in autumn, a reduced intensity cutting regime (incremental cutting) resulted in an average reduction of one species and a small shift towards plants typical of less fertile conditions, compared to cutting back to a standard height and width. Hedgerow plots cut in late winter had a plant community typical of slightly shadier conditions, compared with those cut in autumn. Hedgerow cutting management can thus alter the richness and composition of plant communities, over relatively short timescales. These results are discussed in the context of longer term trends in hedgerow plant communities across northern Europe, and conservation management funded under agri-environment schemes.