How does LUC affect my nitrogen limit?
The National Policy Statement for Freshwater Management was released by the government and instructed regional councils to come up with a system to improve freshwater in their regions. They left it up to the councils to work out how they’d do that in their area, so we’ve ended up with a number of different rules in different parts of the country.
One of the key differences is in the way councils set rules to manage Nitrogen loss.
Areas like Taupo and Canterbury used an approach called “grandparenting” where they looked at modelled farm losses and set a limit based on what a farm was losing a year or so before anyone knew the changes were coming in, assuming no one would have had a chance to artificially inflate their losses that way. This could be hard for farms who had large areas under trees, perhaps were late in a succession transition, or already low leaching for other reasons. It meant that a low intensity farm next door to a high intensity farm would be given a much lower limit, and people were almost seen to be rewarded for dirty farming.
Hawkes Bay Regional Council have decided to use a system based on “Natural Capital”, using Land Use Capability (LUC). Your farmland is assigned a value between 1 and 8 based on the classification. LUC areas 1-4 are really good land, suitable for cropping and more intensive activity. LUC areas 5-7 have increasing limitations to productivity and are suitable for pastoral farming. LUC 8 is only suitable for conservation. The council has assigned a limit for N loss in kg/ha/year for each classification. So LUC 1 land has a higher limit than LUC 7 land, but because of Hawkes Bay’s low rainfall, most farmers find they’re already within the limit, as you don’t tend to farm intensively on land that has a lower N limit due to topography, climate or erosion limitations.
Thinks to note about this N limit are:
- it’s the only “hard number” in the plan you need to stay within
- Most mapping has been completed at a national scale of 1:50,000 and it may be worth investigating whether paddock scale LUC remapping would benefit your farm
- This is a limit, not a target. The limits are generous for pastoral farming and if everyone farms UP to their limits, freshwater quality will deteriorate
Your farm could benefit from paddock scale remapping of land use capability. Contact us for more information.