WBC can provide an important food source for a range of farmland birds, including many of the Red listed Birds of Conservation Concern. The loss of winter food sources, particularly crop and weed seeds, due to changes in farming practice has been identified as a key factor in the decline of farmland birds. WBC recreates the winter food sources that were once widespread on farms, and enables a range of weeds to establish. The presence of weeds in WBC greatly increases its value but a compromise needs to be reached with the requirements of the crop, particularly during establishment.

   Kale and quinoa are the two crops that support the greatest range of species in the highest densities. These crops replicate the wild crucifers and goosefoot weeds that form a major component in the diet of many farmland birds. Kale and quinoa should be included in the majority of general purpose mixes, with the addition of oats and oil seed rape.

   A rotational mosaic of WBC of different ages and seed mixes should be established on farms to provide a constant range of seed type

   The Scottish climate and growing conditions means that several WBC crops widely grown in England are not suitable for Scotland, such as maize, millet and sunflowers.

   The requirement under set-aside rules for two crop types to be present in the mix for up to two years means kale needs to be included as it is one of the few available biennials. Most other crops are annuals and disappear from the WBC in the second year, unless they re-establish as volunteers. WBC can be sown as an annual crop.

   The location of the WBC influences the range of species using it. Siting it next to a hedge or woodland encourages woodland edge species but discourages birds such as skylark and corn bunting, which prefer open environments.

   Currently WBC only accounts for 1.5% of the total area of set-aside in Scotland. To increase the area there needs to be an incentive to farmers in terms of a price differential to cover the difference between the cost of WBC and the much cheaper and more attractive alternative set-aside options of green cover and natural regeneration. However, when payment has been offered by FWAG/RSPB there have been problems with the “lucrative use” clause. A recent announcement by SEERAD indicates that payment can be provided by FWAG/RSPB to cover this cost and seed can be provided in lieu of payment, but this will only benefit a few farmers participating in local projects.¨

   The requirement to have the cover sown by 1st May is a particular problem, particularly in wet springs when spring sowing is delayed, leaving no time for sowing WBC. This date does not apply England despite the earlier season, and it would encourage more farmers to sow WBC if the date was later. The rules governing management, such as use of fertiliser, also need to be revised to make them more practical.

¨ Refers to projects run by local FWAG groups and may or may not be available in your area.