Farmers only need to use simple measures to help meet government targets on biodiversity, according to the results from a five-year £1m project.
Farm4Bio project leader Jim Orson, technical director of The Arable Group, told advisers at last week’s HGCA Agronomist conference that a simple approach using correctly managed sown covers on uncropped land could make a “real impact” in attracting birds and other wildlife.
Mr Orson said two covers had provided the best value for biodiversity in the project.
Grassland mixed with wild flowers and mixtures providing wild bird cover, such as triticale, winter vetch and fodder radish, had provided a better habitat for invertebrates and increased numbers of beneficial insects compared with grass margins.
Flower-enhanced grassland had also increased bee numbers, although pollen and nectar mixes were more effective, he said.
“Every farm can produce a difference. A simple approach is all that is required,” said Mr Orson.
That could involve sowing the grassland/flower mix, costing around £140/ha spread across a number of years, in awkward corners that were difficult for machinery to reach, and winter bird food covers costing £90/ha annually around the edges of fields, he suggested.
For the latter, autumn sowing would increase insect bird food early in the spring, and if fodder radish was included would also provide insects through until early April. “If food runs out earlier you may need to use supplementary feeding.”
Both options were included in the CFE options, he pointed out.
The project suggested that just 2ha out of every 100ha needed to be sown with managed margins to avoid zero counts for various bird species. “And once you’re above 4ha you’re making a big difference to bird numbers.”
Mr Orson said farmers should target specific types of birds they want to attract, information that should become available through the Campaign for the Farmed Environment.
“We found that birds respond to boundary features. The skylarks decrease with the more boundaries you have, but most other birds increase,” he explained.
Butterflies, bees and invertebrates preferred strips close to field edges, but there was no threshold area. “The more the better.”
But he warned farmers against becoming “biodiversity-crazed”. Other objectives, such as water protection, also needed to be met, he said.
For more information on the Campaign for the Farmed Environment click here.