In recent years, larger fields and a reduction in non-crop vegetation have contributed to steep declines in farmland flowers and the organisms that depend on them.
LEAF is pleased to be one of the partners in the Ecostac project. This project’s key aim is to “develop a seed mixture for perennial field margins that has the potential to optimise pest control, pollination and conservation benefits while minimising potential risks for vegetable rotation schemes”. This seed mixture contains selected flowers to provide bees, hoverflies, parasitiod wasps and other pest predators with abundant nectar and pollen, as well as alternative prey and lodgings for the winter. For farmland birds, plants that produce abundant seed and provide insect food for fledglings have also been added. Growers will be pleased to hear that any “bad blooms”, likely to support diseases, aphids or other crop pests, have been excluded from the preferred perennial field margin seed mix.
Though only half-way through its 4-year experimental phase, results from the project have already shown that the seed mix used can support a wide range of beneficial insects. Here’s the results so far:
- Many more bees, hoverflies and parasitoid wasps have been observed in experimental flowering margins than in grassy ‘control’ strips in 2010 and 2011
- As margins have matured, this pattern has strengthened from year to year
- The flowering field margin prescription also seems to have suppressed pest numbers into crops, with significant average yield increases in 2011 of 15-40% for peas, wheat and cabbage near to flowering margins (see figure below)
- Probably as a result of improved ‘biological pest control’ at these sites