Although widely considered nuisance plants, scientists from Hull have proven that weeds are actually vital to the existence of a great number of farmland species of birds, insects and animals. image expired

The researchers found that seeds and flowers produced by common farm weeds are an integral part of the ecosystem, supporting over 330 species of animal. By creating “food webs” linking all farmland creatures with seeds typically found on farms, the scientists showed the extent to which birds, insects and larger animals rely on plants commonly considered as ‘weeds.’    

Dr Darren Evans, biologist at Hull, said, "We understand a lot about farmland birds and mammals, but little about the plants and insects that underpin them. In this study, we discovered not only the importance of weed and non-crop species for many farmland animals but that the vast majority of seed-feeding animals on farms are insects, which are often overlooked by conservationists."

Uncultivated, semi-natural habitats on farm land, such as hedgerows and woodlands, promote biodiversity. However, the researchers said further small changes to cropped areas, such as allowing some weed species, could prove beneficial in increasing the quantity and variety of seeds for wildlife, maintaining a healthy environment.

Dr Evans, who led the study offered an overview and explained the implications of the work for sustainable land management policy. He told Farming Online, "Our study focussed on the birds, mammals and insects that fed on over 120 species of seeds and berries found on a typical organic farm. We found that more than 330 species use the seeds as a food resource, the overwhelming majority of which are invertebrates (82per cent) relying predominantly on non-crop and weed species. We found that small changes to

"farmland management, such as carefully allowing some weeds in cropped areas, are likely to have significant, positive knock-on effects for farmland ecosystems. Moreover this might improve natural pest control, although more research is needed. We suggest that rather than focussing agri-environment scheme conservation efforts on a small number of charismatic species, such as birds, an alternative approach is to understand and manage the complex network of species interactions on farms. This is still a distant target, but we look forward to a time in the future when it may be possible to manage farmland habitats more precisely, both for food production and for biodiversity."

As part of the European Commission’s proposals for the reform of the Common Agricultural Policy leaked last month, farmers will be expected to devote at least 5 per cent of their land to ecological purposes, such as fallow land, buffer strips as well as maintaining permanent pasture.