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Is the Tide Eventually Turning for Clover?


Dairy farmers are regularly asking their advisors what they are going to do about fertiliser next spring. They are aware that Nitrogen fertiliser looks to be scarce for next spring and if available, it will be at inflated prices. Teagasc Advisor John Hardy has advice on the some options for coping

Grass is the cheapest feed

Dairy Farmers are very well aware that grass is our cheapest feed costing 8c/kg compared to dairy nuts costing 35c/kg. Certainly if available even if at inflated prices Nitrogen fertiliser will be bought and spread next year by dairy farmers. So what if anything can farmers do to mitigate against the risk of inflated input prices?

  1. Soil sample - If you don’t already have them get soil samples done in December or January. We know that Nitrogen applied to ground that is low for Lime, Phosphorus or Potassium is only 30% effective compared to Nitrogen spread on land with good soil fertility which is 60% effective.
  2. Carry a grass cover over the winter appropriate to your 6 week calving rate: 600kgDM/Ha for 6 week calving rates below 70% and 700kgDM/Ha for 6 week calving rates above 70%.
  3. Slurry - Make effective use of slurry next spring. Try to target 2000 gallons/acre slurry on your low covers in February and another 2000gallons/acre slurry on your grazed paddocks in March. The Nitrogen in this if spread with LESS will be the equivalent to half a bag of urea/acre

In the short term this is all that can be done to insulate ourselves from rising Nitrogen prices. In the long term however there are solutions.

White Clover Research

In 2010 Teagasc Moorepark initiated a research programme investigating the benefit of incorporating white clover into perennial ryegrass pastures for high stocking rate systems of milk production. In 2016 the results were published. The headline findings were:

  1. Over three years a grass-clover system receiving 150kg of N/ha produced similar grass DM production/ha as a ryegrass only system receiving 250kg of N/ha (14.4 vs. 14.5t DM/ha respectively).
  2. Animal performance has been consistently high in the grass-clover systems at similar stocking rates; +58 kg of MS/cow higher over two years in the Clonakilty study; +29 kg MS/cow over three years in the Moorepark study.
  3. Preliminary results to-date indicate that incorporating clover into a ryegrass pasture at similar or reduced nitrogen application rates had no effect on nitrate losses to ground water; research carried out at Solohead showed that replacing fertiliser N with white clover fixed nitrogen substantially lowered nitrous oxide emissions

Why have farmers not incorporated clover?

Since 2016 John has asked farmers how they can afford to choose to ignore implementing a clover incorporation strategy on their farm given the overwhelmingly positive research. The answer varies but it centres around three concerns:

  • Nitrogen is available and relatively cheap
  • You could get a cow dead with bloat
  • Since clover doesn’t grow below 8 degrees Celsius more silage needs to be fed in the spring

So now that there is an issue with Nitrogen, is it time to develop on farm mitigation strategies to deal with bloat & lower spring covers in the same way we do with other issues such as grass tetany or milk fever?

If you believe so then contact your agricultural advisor and seek the best advice as to how you will incorporate clover into your swards next year. “There is nothing to fear but fear itself!”