Clover has finally come of age. Escalating nitrogen costs, the impact of NVZs and years of belt tightening have finally persuaded livestock farmers that they should make more use of its nitrogen fixing ability.
Trade stands at this year’s Grassland and Muck 2008 Event reported a stream of enquiries from farmers wanting data on clover’s benefits and financial value. “A good stand of clover is worth 200kgN/year. At today’s fertiliser prices of £300/t (34.5%N), this equates to £180/ha/year saving in bag nitrogen,” said grassland consultant Duncan Findlay of United Phosphorus.
Over the average ley’s five-year life span, this works out at £900/ha. Yet these costings were based on early 2008 figures, he pointed out. “Fertiliser prices are forecast to continue to go up and farmers need to budget for at least £5/t/month increase.”
Weed control concerns
According to UPL’s grassland performance survey of 250 dairy farmers, new reseeds rich in clover typically suffer 10-20% in lost yield as a result of chickweed infestations. Almost 20% of farmers said they broadcast or slot seeded clover after grass had been established due to weed control concerns.
However, while Mr Findlay said that although chickweed was the key robber in a new ley, there were now safe herbicides, such as Alistell, to control it and help grass to establish without knocking out clover. “Later on, there are also safe products for the more difficult weeds such as thistles and buttercups,” he added.
Grazing in 2009
Clover sown now will be ready for grazing in spring 2009 as it takes 8-14 months to fully establish, said Advanta Seed’s Ian Misselbrook. Getting clover seed, which is tiny and light, into swards is made easier by using pelleted seed. “There is still time to establish it as there is moisture in the soil – any time up to September – although after second cut is best, to avoid competition from rapidly growing grass,” he suggested.
“Keep sheep away as they selectively graze clover and be aware that if a lot of peas are grown in the area, clover weevil will migrate and could affect establishment.”
For the best clover varieties, producers should check out the lists in the new Herbage Varieties Guide, published by NIAB, the British Society of Plant Breeders and the British Grassland Society. This provides yield and ground cover data for 28 red and white clovers, plus yield and D-value for over 100 grasses.