Farmers should use a combination of methods to control rushes on agricultural land and keep it eligible for the Basic Payment Scheme.
Speaking at an on-farm event at Claudy last Thursday, CAFRE’s Terence Henry emphasised that drainage, soil fertility and grazing management are just as important as using chemicals to keep rushes at bay.
“Mulching or flailing offers a quick fix to controlling rushes. But land has to be flailed every year to keep land eligible. Chemicals give slightly longer control over a couple of years. But again, there will be young seeds germinating after the chemical treatment, so the rushes will continue to grow,” he said.
Henry advised the ideal approach is probably to mulch the standing rushes, and as they regrow, graze the grass as low as possible and then target with chemical treatment.
“Use a weed wiper, rather than a boom sprayer. Weed wipers place chemical directly on rushes, so there is less chemical wasted and other plants are not killed off. Weed wipers can also be used on windy days, whereas the boom sprayer cannot,” he said.
Henry also outlined the importance of liming soils, as well as phosphorus and potassium applications, where required, as rushes thrive on low fertility soil.
Liming also increases earthworm populations, which naturally improve drainage and excrete calcium, further helping to lift pH.
Poaching soils should be avoided, especially in spring and late autumn as rush seeds lie dormant for up to 60 years. “Poaching disturbs soil and stimulates rush seeds to germinate,” said Henry.
When it comes to chemical treatment, the clear advice from NI Water is to use glyphosate, not MCPA.
“Glyphosate is licensed for weed wipers. MCPA is not. MCPA does not bind to the rush as well as glyphosate and is quickly washed off and ends up in water courses” said Rebecca Allen.
She maintained that one capful of MCPA entering a water course can be detected 18 miles downstream, and it remains in the water for six weeks before it breaks down.