White clover reseeding means less N next year
WITH good grass availability on most farms, consider reseeding or overseeding less productive pastures with white clover to cut fertiliser nitrogen use next year.
So advises Neil Adams of Axient (formerly Genus Management).
"The average dairy farm uses 200-220kg of nitrogen/ha. White clover could produce an equivalent amount of fodder with no nitrogen which is more environmentally friendly," he says. He also stresses that clover improves sward digestibility and palatability, and can increase sward life by filling in the gaps normally filled by weeds.
When establishing a new ley, ensure clover seed is broadcast and not drilled. Alternatively, spray an existing sward with low rate paraquat to open it up and sprinkle clover seed on the surface.
Mr Adams advises using a mix of clover varieties at a seed rate of 3kg/ha (1.2kg/acre) and sowing before mid-September.
"Improved clover varieties out-yield Huia by up to 50%. They are also more cold and nitrogen tolerant, with bigger leaves and compete better with grass." Large leaved types are best for dairy animals; for sheep use smaller leaved ones, says Mr Adams.
Robin Hill of Glos-based Cotswolds Seeds agrees that there is still time for successful establishment.
"Blitz the field with stock for about a week to take the grass down tightly and leave an open sward to help the clover establish."
Alternatively, spraying with 1.4 litres/ha (0.6 litres/acre) of gromoxone will to take out annual meadow grass and other unproductive weed grasses, he suggests.
When the sward is more open the clover seedling has plenty of light to develop. It is also important to keep grazing after sowing – again to get light to the seedling.
Mr Hill also suggests sowing a mix of varieties, including AberHerald which has the capacity to grow at lower temperatures during winter, and for dairy producers a larger leaf variety such as Alice. Sheep producers should include a proportion of smaller-leaved genuine wild white clover – such as Kent or S184 – in the mix. "These clovers withstand continuous sheep grazing, and are good colonisers," says Mr Hill.n
• Reduce N use.
• Lift palatability.
• Longer sward life.