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Precision agriculture

Precision agriculture

A Canterbury farmer has been able to reduce input costs and improve environmental outcomes using a nitrogen sensor as part of the Next Generation Farming project.

Roscoe Taggart achieved greater efficiency through the use of a new Yara N sensor on his family’s 730-hectare arable and sheep farm in Cust over the last two years.

This year’s harvest was been a mixed bag due to wet weather conditions. However, some crops still produced well.

"We have just harvested our evening primrose and it’s been surprising to see how well it has done, especially for a paddock that was pretty wet early on. We’ve exceeded our target for the seed yield off it."

Taggart tried maize for grain for the first time this year and was pleased with the result. He will plant maize again next season as it works well in his crop rotation and returns potassium to the soil.

"It’s a crop with nice deep roots so it breaks up the soil nicely. While it does require a bit of fert up front, you end up returning a lot of K to the soil instead of removing it, which is what happens if you grow it for silage instead of for grain.

"It also works well because we harvest it in early June, so it extends the season out further which means we are harvesting from November through to June,” he said.

For Taggart, one of the most important precision agriculture tools was the Yara N sensor. It helped him reduce nitrogen fertiliser use by about 80kgs this season.

"It’s been a game changer for us, especially using the N sensor in absolute mode, where the N sensor decides how much fertiliser to apply. We’ll keep using it in absolute mode because it minimises our N use which is important not just in terms of cost savings but also environmental impact."

Taggart was learning about mineralisable N in the soil, which is released from organic matter throughout the season, to reduce his use of nitrogen even further.

"The soil itself can supply a good amount of mineralisable N and we just need to work out when the N in the soil will be available for the plant to use and we believe this will reduce our use of N fertiliser even further."

One thing that surprised Taggert over the last two years during the N sensor trial was the amount of variability he found throughout his farm.

"There’s more variation in our relatively flat, uniform farm than I ever could have imagined. Looking at the maps that come out of the N sensor there’s no consistency in paddocks that, before using the sensor, I would have thought of as very consistent."

Taggert said he believed precision agriculture was critical to the future viability of farming in New Zealand.

"Precision ag makes your farm more efficient and there are some real social, environmental, and economic benefits that you don’t realise until you get into this.

"I never thought too much about future generations until I had kids of my own. You want them to have the opportunity to farm where you farm. That’s when you start looking around the place and thinking about how to make farming sustainable for the next generation.

"If I can leave this land in as good as or a better condition than I found it then I will be happy with what I have achieved."