Autumn is a key time to start planning spring-sown bird food crops. In the third in our CFE series, Philip Case looks at the options and how to establish them
Farmland bird numbers in England have continued to decline, increasing the pressure on the farming sector to do more in promoting wildlife through the Campaign for the Farmed Environment and head off the threat of compulsory set-aside.
DEFRA figures published this summer show populations decreased by 3% between 2008 and 2009 and are now at their lowest-ever numbers, 53% lower than the 1966 starting value.
One way to help reverse this is for more growers to adopt some of the more demanding options under environmental stewardship schemes, such as establishing bird food crops. The aim is to provide dwindling populations of farmland birds, such as tree sparrow, yellowhammer, and corn bunting, with an essential supply of food during the critical winter period and into the spring.
The first factor to consider is which areas to take out of production. Alex Butler, an adviser with the Game and Wildlife Conservation Trust, suggests targeting less productive ground first, such as awkward field corners, small fields and wet areas, preferably next to hedges. But some farmland birds, like skylarks and lapwings, require in-field nesting habitat, he notes.
One recent change is a more flexible ELS prescription, which means growers can now grow different crops in separate drill widths or blocks for the Wild Bird Seed Mix (EF2) option.
Growers are still required to sow three small seed-bearing crops (barley, triticale, kale, quinoa, linseed, millet, mustard, fodder radish and sunflowers). The mix, according to the handbook, should include any three of these plant species, but does not have to include brassicas and/or cereals.
For example, a mix could consist of quinoa, linseed and sunflower – none of which are brassicas or cereals. However, the mix could contain three brassicas (kale, mustard and fodder raddish), or three cereals (barley, triticale and millet).
These changes make management of these mixtures more straightforward in terms of drilling and agronomy. “Having different crops in different blocks also allows inputs to be varied; kale recieves a minimum of 60kg/ha of N whereas quinoa only half this.”
Wild bird seed mixtures (EF2/OF2) are mixes of seed-bearing crops that benefit species ranging from grey partridge to linnet (see diagram). There are also mixes that provide driving cover for gamebirds for farmers with a shooting interest.
There is a wide range of potential components of wild bird seed mix. “Second year kale is a good source of winter food for various birds,” Mr Butler says. “Quinoa is popular with finches and buntings and fodder radish provides seed into spring when other food sources have been exhausted.”
The umbrella-like canopy of kale also provides shelter in winter and keeps the ground moist during the summer, allowing thrushes to collect slugs and insects with which to feed their chicks.
Poor crops provide little seed and so good crop husbandry is critical. And achieving a quick establishment leaves less time for the weather and pests to ruin a crop during the vulnerable early emergence stage.
Most wild bird seed mixes are sown in the spring, a time when farmers are generally less frenetic than in the autumn. “You need a good seed-bed which is not too ‘cloddy’, as clods carry the potential for slug problems and seeds dying out,” says Mr Butler.
Drilling rates and depths vary according to the crop. Generally the larger the seed the deeper it is sown. Whereas maize should be drilled at 5cm plus, kale, quinoa and millet need only be drilled at 1-2cm depth.
Mr Butler says fertiliser is critical if you want to get your crop away quickly. “If you want your crop to be established quickly and produce a lot of seed, put the required amount on nitrogen on.”
“I always recommend at least 100kg of nitrogen/ha. GWCT trials have shown that yields of kale seed can increase by as much as six times, by increasing nitrogen inputs from 30kg/ha to 90kg/ha.
P and K levels are also important and he recommends getting soil tested. “A P and K index of 1-2 is good and the pH should ideally be 6.5-7,” he adds.
Mr Butler says 12t/ha of manure can “work wonders”, particularly on light droughty soils, as it also helps with moisture retention.
Timing and rates
Late April to the beginning of May is a good time to drill, when the ground is warming up and there is still moisture in the top soil.
The RSPB recommends the following seed rates: Kale 5kg/ha, quinoa 10kg/ha, rape 7.5kg/ha, cereal 125kg/ha and linseed 60kg/ha. If part of a mixture, figures should be divided by the number of crops in the mix.
Growers should consider seed treatment as an option as this aids establishment. “Treating kale seed with products like Combicoat (carbosulfan) and Ultrastrike will guard against flea beetle,” says Mr Butler.
“It is worth sourcing seed from a cover crop specialist who will offer varieties specifically bred for the purpose.”
Pests and weeds are the key problems that can result in patchy crops with a low yield of seed for birds or even just a mass of weeds. Growers can become frustrated ending up with patches of fat hen and redshank. ELS Wild Bird Seed Mix (EF2) prescriptions, for example, allow the spot-treatment of weeds such as creeping thistle and broad-leaved dock.
Also of note, the 2010 ELS handbook allows agreement holders to rotate these mixes around the farm, which allows ground to be cleaned up, if weeds become problematic, and put back into commercial crop production. With pests, it can prevent the build-up of diseases such as club root in brassicas.
To conclude, Mr Butler says: “Watching a flock of linnet feeding on a well grown wild bird seed mix is exceedingly rewarding; even more satisfying is growing the same conservation crop next to a clean, high-yielding and profitable crop of wheat.
Demo plots to increase bird habitat
Harper Adams University College is hosting more than 80 demonstration plots to encourage growers to introduce more crop options on their farms to increase farmland birds and provide habitats for insects.
The plots are in their first year and they are being managed by Natural England to demonstrate options and management of options under environmental stewardship and CFE. They are also being used to investigate different seed mixtures and their management, including nitrogen fertiliser rates and best practice.
Geoff Howe, Natural England arable adviser for West Midlands, said: “The plots have been established to give growers the opportunity to see these wildlife
options first hand and to encourage them to introduce them on their farms.
“Growers know how to get good yields on their commerical crops and the aim of the wild bird seed mixes is no different. We need to ensure good seed yields for overwintering farmland birds.”
Natural England regularly hold farm walks around the site, with the next event planned on 4 November. For more details, email firstname.lastname@example.org or telephone 0300 060 1695.