Growers interested in countryside stewardship can get a grant for a “two-year sown legume fallow” (option AB15). However, the long-term presence of legumes in the soil may build up pathogen pressure. Best practice suggests a rotation of one in six years, allowing at least five years between pulse crops to ensure minimal build up of pest and disease pressure in the soil.
The Processors and Growers Research Organisation (PGRO) has been studying the impact on pest and diseases, when using legumes in catch and cover crops since 2016.The study has found that the use of a catch or cover crop has a positive benefit on the pea crop and no negative impact on vining peas.
Growers can take steps to integrate Countryside Stewardship option AB15 into their rotations, while minimising the potential pest and disease risk to pulse crops. AB15’s two-year sown legume fallow option must comprise six flowering species, based on alsike clover, bird’s-foot trefoil, black medick, common vetch, lucerne and red clover. The mixture is to be sown at 15 to 20kg/hectare, as appropriate for the described soil type.
Roger Vickers, chief executive officer, PGRO said, “For those wishing to minimise the potential risk of legume disease build up but also keen to take advantage of the stewardship scheme, one approach might be to minimise the content of common vetch and red clover and maximise the opportunity to include grasses or alternative flowering perennials to make good the seeding rate.”
It is advised that grasses such as cocksfoot, perennial ryegrass or timothy may be included to help smother blackgrass and other competitive grass weeds.
Red clover and common vetch pose the most significant risk, due to their association with foot rot pathogens and stem and bulb nematodes. “Options for adaptation of AB15 seem to exist, the mixture may be adapted by lowering species content and it is also apparent that the total quantity of flowering plants in the mixture may be reduced by the inclusion of prescribed grasses,” Mr Vickers adds.
