1. Intensive farming has contributed to the serious declines in the abundance and diversity of bumblebee and butterflies.
2. UK agri-environmental policy aims to conserve and restore bee and butterfly populations by providing foraging habitats on land taken out of production.
3. Recent research suggests that current management prescriptions are failing to provide pollen and nectar habitats of sufficient quality and longevity in the wider countryside.
4. We report the findings of a range of integrated experiments to determine the best means of creating and managing pollen and nectar habitats on arable farmland in the UK.
5. Experiment 1: examines the flowering performance and persistence of a range of Red clover varieties managed under different cutting regimes.
6. Over four years the agricultural variety of Red clover Milvus and the wild variety from Somerset were the most persistent. Summer cutting (June) with or without an autumn cut significantly enhanced the cover of Red clover and the abundance of flowers. However, this cutting regime reduced cover and flower abundance of other sown legumes, such as Birdsfoot trefoil. Removal of cut material significantly increased the cover and flower abundance of sown broad-leaved species.
7. Experiment 2: investigated the performance of pollen- and nectar-rich broad-leaved species sown with grasses of differing competitive ability.
8. The typical practice of sowing tall and competitive grass species, such as Meadow Fescue, Timothy and Rye grass, significantly reduced the cover legume species. Persistence of sown legumes was significantly better in mixtures sown either without grasses, or with fine-leaved grasses, such as Crested Dogstail. Winter application of the graminicide propyzamide (Kerb Flo, Dow AgroSciences Ltd.) in year 3 reduced competition from grasses, increased cover of sown dicots and undesirable weed species (Cirsium sp.).
9. Experiment 3: compared the foraging preference of bumblebees and butterflies for a range of annual crop species sown in wild bird seed mixes with perennials sown in pollen and nectar seed mixtures.
10. In year 1 flowers of annual species were much more abundant than those of perennials. In year 2 flower abundance of perennials, such as Red clover and Sweet clover, were similar to the annual species. There were marked differences in the timing of peak flowering between species: Crimson clover flowered in late May, Fodder radish in late June, Borage, Phacelia. Red clover and Sweet clover in late July, Sunflower in late August. Short-tongued bees showed a marked preference for Phacelia and Borage. Long-tongued bees showed a significant preference for Red clover, Crimson clover and Sainfoin
