The best kept secret in organic farming
Red and white clovers are the magic bullets for organic beef
Published 16/03/2016 | 02:30
The "best kept secret in Ireland" for generations has been revealed in the nutrient boost that red clover can deliver to beef producers from ensuring a generous measure of the plant in silage.
It was among the key words of advice to the hundreds of farmers at the Teagasc organic beef open day on the farm of John Purcell, at Golden, Co Tipperary where the use of red and white clovers have become a key ingredient in both pasture for grazing and forage for silage to maximise performance and increase profitability.
Clover is the "cornerstone of organic farming and the engine that drives productivity", Patrick Conaghan, Teagasc, Oakpark told farmers.
He explained the capability of the plant to convert atmospheric nitrogen into a plant usable form with annual nitrogen fixation of 150-200kg/ha achievable from swards with high red clover content with yields of 12 to 15t DM/ha achievable when grown with ryegrass.
However, the life span is typically two to four years at farm level and the main role for red clover is for silage production as continuous grazing will reduce yield.
It is also recommended that silage cutting level is set at 7-8 cm above ground and use of heavy machinery on red clover sward in wet weather should be avoided.
"It has a high protein content of 16 to 20pc and the feeding value of red clover silage is higher than grass silage resulting in greater animal intakes and higher levels of animal performance," he explained.
Results from Teagasc at Grange found that the mean live weight gain in beef production on red clover silage was 1.04kg/day, compared to 0.83kg/day where white clover silage was fed and 0.59kg/day on grass silage.
Elaine Leavy, Teagasc, Grange said that the objective for organic beef production should be to work off a predominantly a forage based diet supplied from the farm itself to minimise the requirement for concentrates. Organic rations can cost up to €500/t but should where possible be supplied from straights which should be available at €300-€350/t.
"Overall the aim of organic beef production systems is to provide an overall balanced diet with the grazed and conserved forages supplying energy and with the protein and grain supplying an extra energy source," she said.
On organic farms the incorporation of white clover in the sward is widely recognised as the driver of grassland production and coupled with good grassland management it is possible to achieve a long grazing season of high quality feed.
James Humphreys, Teagasc, Moorepark said that on organic cattle farms the high cost of concentrates strengthens the incentive to maximise on pasture use in the diet and white clover "is the key component of organic pastures because pastures that contain white clover can have twice the productivity of swards that don't".
He pointed out that "clover forms a symbiotic relationship with N-fixing Rhizobium bacteria that can supply up to 200kg N/ha per year under Irish conditions".
He pointed out the growth rate for white clover is low until late March, accounting for 5-15pc of sward during February and March, while from mid-Summer onwards approximately half of the sward is composed of clover and N fixation is at its strongest.
The use of both red and white clover in pasture and silage comes with some health warnings.
Because red clover can contain up to 1pc of oestrogenic compounds, which can lower ewe fertility it is not recommended to allow breeding ewes to graze red clover swards or eat red clover silage for up to six weeks before and after mating.
In terms of grazing for livestock the risk of bloat is reported to be higher with red clover than white clover.
The risk is higher in cold and wet weather or when animals are particularly hungry and likely to have a higher intake.
The advice is "never allow hungry stock to gorge themselves on clover rich pasture".