Fertiliser product recalls leave farmers without major tools, Tim Cronshaw and Ali Tocker report.
Dairy farming has lost one of its best tools for reducing both nitrate leaching to waterways and greenhouse gas emissions.
Fertiliser co-operatives Ravensdown and Ballance Agri-Nutrients have told farmers to immediately stop using, until further notice, their respective products eco-n and DCn.
The products contain an active biodegradable ingredient known as dicyandiamide or DCD, which has been added to an international list of substances that must be tested for.
The moves arose after tests on whole milk powder detected the occasional presence of low levels of DCD. It is seen as a trade issue, not a food safety issue.
Federated Farmers Waikato president James Houghton said loss of DCD was a blow to farmers, as it had been having good impact environmentally.
"It is one of the major tools out of the toolbox. This highlights to the community how much we need good science to progress to a better environment," Houghton said.
Hamilton-headquartered DairyNZ said it supported the proactive moves by the fertiliser co-operatives.
"But we hope some pragmatic solutions can be found that enable the product to be back on the New Zealand market as quickly as possible," chief executive Dr Tim Mackle said.
"It's a very useful tool in terms of managing nutrient loss from farms."
DairyNZ had a lot of research underway seeking other ways to mitigate nitrogen loss, so not everything was hanging on one tool.
Ravensdown said it was suspending sales and use of its product, eco-n, for the rest of the calendar year because use of DCD was becoming a possible trade risk.
Chief executive Greg Campbell said research showed there were no food safety issues with DCD.
It had been safely used around the world for 30 years, and Ravensdown had taken the precaution of suspending its product to retain New Zealand's dairy export reputation, he said.
Ballance spokesman Warwick Catto said Ballance had not sold DCn since July 2012 and had not promoted its use on pastures since late 2010. The co-operative would not reintroduce any DCD-based products to the market until the potential international trade issue of milk residues was solved.
Ministry for Primary Industries spokeswoman Carol Barnao said as soon as the ministry knew that even very low levels of DCD residues found in milk may present a trade issue, it set up a working group to assess the impact, "even though there is no food safety concern associated with the use of DCD".
Food regulators around the world are tightening testing in line with more demanding markets.
"Given DCD's environmental benefits, the working group will continue to assess its future use in a way that meets trade requirements," Barnao said.
Farmers will have to rely on testing, nutrient planning and advice, plus precise fertiliser application, to keep nitrates down. Fairfax NZ
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