Farming with less N

By Ants Roberts.

Reducing reliance on N fert.

AROUND 25% OF DAIRY farms used more than an average 190 kg N/ha over the years 2013-2018, with even greater proportions of dairy farmers in Canterbury and Southland exceeding this amount.

All pastoral farms are now limited to an average of 190 kg N/ha/year. In the quest for increased productivity a proportion of farm systems have been set up with a permanent mismatch between feed supply and demand which has been met, in part, with systematic N applications after nearly every grazing.

For some, there will be considerable reduction in the reliance on N fertiliser to supply critical feed
throughout the lactation.

In some ways, there is the opportunity to reassert the importance of the legume e.g., white clover in the
pasture mix to supply some of the N required to drive pasture production.

In some dairy systems, we have lost the ‘art’ of managing the symbiosis between grasses, herbs and N fixing legumes. However, there are also a number of other levers that farmers could consider, in a variety of combinations to suit their own personal circumstances, to assist in farming with less N fertiliser inputs.