Diverse pastures can outperform artificial fertilisers
Published 20/04/2016 | 02:30
The use of red and white clover in the production of pasture for grazing are cornerstones of organic production. However, John feels that there is even more potential to be gained by introducing other diverse plants into the mix.
"Working from my own experience and backed up by research from Teagasc in Moorepark, white clover has the potential to grow as much grass as you can produce from high inputs of artificial nitrogen.
If there is too much nitrogen added clover can become lazy, so by removing the nitrogen inputs the clover really kicks in. Last year I added 240kg/ha of nitrogen and grew 13t of grass DM. I am anticipating a drop this year, but I know that white/red clover and grass mixtures have the potential to grow 13 to 15t of DM with no artificial N. I am also using a diverse mix of herbs in the pasture."
John has started by reseeding four acres but has plans to reseed more of the farm in this mix. It is essentially 35pc herbs and 65pc mixed grasses. "Ryegrass is too limited in its nutrient extraction potential, it has a very short root system, by introducing plants with deeper rooting systems you can access more nutrients in the soil," he said.
Key to the mix are plants such as sainfoin (a deep rooting legume that will fix nitrogen), birdsfoot trefoil (which like sainfoin contains condensed tannins which have been identified to prevent bloat), chicory (deep rooting and a valuable anthelmintic), ribgrass, burnett, sweet clover, red clover, yarrow, sheep parsley and various grasses such as timothy, meadow fescue and ryegrass.
John quotes pioneering organic farmer Newman Turner, who described the herbal ley as 'my fertiliser merchant, feed merchant, and vet all in one'.
I want to create diverse pastures on the farm that will maximise capacity. I would love to see an organic research farm working on the potential for herbal leys in Ireland, as we can grow diverse pastures with numerous benefits" he says.