Thursday, 28 February 2019

Smarter urea means farmers can buy less nitrogen


Choosing products coated with a special urease inhibitor is one way for farmers to reduce the total amount of purchased nitrogen needed on farm.

Compared to uncoated urea, these coatings reduce the amount of nitrogen lost to the atmosphere by 50% especially in hot and dry conditions. While this ‘smarter urea’ is 7% more expensive than uncoated urea, using the coated version means that less nitrogen needs to be purchased to achieve the same pasture response.

Combining this with other good farming practices reduces the total tonnes of N needing to be purchased per farm which helps the farmers’ bottom line and reduce risks of environmental impacts.

Nitrogen use efficiency is a good way that farmers demonstrate responsible nutrient stewardship. There are three main ways nitrogen investment can end up in thin air. So who are the culprits?

  1. Prevailing dryness
    Bone dry soil with a dry wind mean the urea granule will sit on the surface and the enzymes in the soil get busy breaking it down into ammonia which leads to the N-loss. This effect will be much worse if there is no plant cover.
  2. No rain forecast
    Short of performing a rain dance, there is little certainty about the onset of summer rain. But one certainty is that urea needs 10mm of rain or irrigation within eight hours of it being applied or more N ends up in the air. With dry conditions set to continue as an El Nino pattern threatens, this becomes a very real but invisible cost.
  3. Untreated urea
    In conditions like those above, an uncoated urea granule will quickly begin losing its N to the air. A coated urea product like N-Protect can help halve losses of N through ammonia gas emission. And in dry conditions, this can be higher than the average 18%. This all has an impact on eventual nitrous oxide emissions.

At Ravensdown, we are seeing farmers tackle their greenhouse gas emissions by considering these three factors and choosing coated urea. Our field-based team are encouraging shareholders to think about their utilisation rates, nitrogen use efficiency and environmental mitigations. After all, a co-operative should be helping its owners apply the right amount rather than the largest amount.