Industry good – DairyNZ

Project to reduce N loss

Virginia Serra

DairyNZ Selwyn Hinds project leader

Since 2018, I have been leading a project working alongside a group of partner farms and their rural professionals in Selwyn and Hinds. We are helping farmers identify ways to reduce nitrogen losses and sharing the changes taking place through partner farm field days through the catchments.

This project was important as farmers in these catchments were required to make significant reductions in nitrogen loss to meet Environment Canterbury rules.

With the national synthetic nitrogen cap now in effect since July, we are seeing more farmers nationwide looking at ways to reduce nitrogen use and losses on-farm.

Farmers looking to make changes can gain insights from the project, as we have seen some great improvements in Selwyn and Hinds.

A recent assessment of 235 farms in the catchments found that 100% reported adapting their farming practices to reduce nitrogen loss; 81% of farmers reported improving their irrigation systems or management; and more than 50% have changed how they use fertiliser and improved effluent management or systems.

Most farmers reported undertaking a Ashburton farmer Phill Everest says the family has already met their 2030 target to reduce N losses by 25% and further reductions will be a significant challenge.

wide range of actions, including using plantain or changing stocking rates, alongside reducing nitrogen fertiliser use.

I know that reducing nitrogen losses isn’t always easy, but this project shows it’s possible and a number of options are available to help farmers adopt changes.

Farmer showcase: The Everest family

Improving their farm environment is a major focus for Ashburton farmers Phill and Jos Everest and their son Paul and his partner Sarah.

“We’ve always been focused on learning how to do things better,” Phill says. “We’ve got to learn fast to make changes, so we can continue to play a key role in contributing to local communities.”

On the Everests’ farm, the family has installed a variable rate irrigation system on one pivot. This allows water to be

Common changes farmers in Selwyn Hinds are making

(by percentage of farms) 0 10 20 30 40 50 60 70 80 90

Irrigation improvements Effluent improvements N fertiliser changes Plant catch crops Use plaintain in pasture Low nitrogen feeds Alter winter crops or practices Reduce stocking rate with DairyNZ

applied in different amounts across a paddock, which reduces drainage losses and nutrient losses.

They’ve also been preparing for the introduction of a new nitrogen cap by reducing the amount of nitrogen fertiliser applied by 35%. This has resulted in a small reduction in milk production this season.

“We developed an annual N application plan, so we knew what our target application rates were each month to meet the new targets. We also used a urease-coated urea product, which reduces greenhouse gas and nitrogen losses,” he says.

The family has added plantain and chicory to their pasture mix and planted 22km of planting and shelter along their drains and fence lines.

The changes mean they’ve already met their 2030 target to reduce N losses by 25%.

Phill says continuing to reduce their nitrogen losses will be a significant challenge for their family and other farmers.

“We’re taking small steps each year and this will allow us to make the best improvements we can,” he says. n

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To read more about the work being done by farmers in Selwyn and Hinds, visit dairynz. co.nz/selwynhinds