Farmers could soon be choosing Entry Level Stewardship options for their pest control benefits as well as conservation value.
Researchers at Rothamsted Research are aiming to identify simple but effective dual-purpose options.
The three-year DEFRA-funded pest control project is assessing four habitat types – flower-enhanced grass, insect-rich cover, wild bird seed cover, and natural regeneration – for their ability to support aphid predators, says project leader Judy Pell.
“We are looking at diversity as well as numbers, and how all this will influence pest control. We are also examining whether big blocks or strips are best, and how many are needed.”
Preliminary results from 2008 show that aphid numbers were lower on farms with extra habitats. This was probably because of increased predator activity. “We found the greatest abundance of enemies in flower-enhanced grass,” says Dr Pell.
“However, the overall numbers of enemies in the new habitats were similar to existing non-cropped areas on the farm, perhaps because they had only been established a short time.”
Wild bird seed cover favoured parasitoids, with numbers three times greater than in other non-cropped areas.
Habitat connection seems important, with 6ha blocks and strips looking better than 1.5ha blocks, said Dr Pell.