Bert Quin talks about the new fertiliser spreading system he has created.

The two big fertiliser companies are accused of quashing a more environmentally friendly method of applying nitrogen, in order to protect profits. Tony Wall investigates for 'Growing Pain' a Stuff series examining New Zealand's dangerous addiction to fertiliser.

Taupō helicopter operator Mark Williams thought he'd hit on the holy grail - a system of applying nitrogen that meant up to three times the grass growth and less leaching.

It was a simple method that had been around for years - instead of applying fertiliser such as urea in a solid, granular form, the product is ground up, water is added to create a slurry, and it's sprayed on pasture from the air or ground.

Known as fine particle application, proponents of the system say it's a far more efficient way of applying fertiliser because more nutrients are taken up by the plant and less is lost to the atmosphere and through leaching.

Nitrogen use has exploded from around 50,000 tonnes in 1990 to 500,000 tonnes today, enabling a similar increase in dairy cow numbers and pollution of waterways.

Advocates of fine particle application say the mixture can be sprayed right up to the edge of streams and rivers, without leaching into the water.

But scientists working for the big-two farmer-owned co-operatives, Ballance Agri-Nutrients and Ravensdown, rubbish the claims and say there's no science to back it up.

Williams, whose Lakeview Helicopters does fertiliser spreading, didn't need convincing though.

A couple of years ago, when the "arse fell out of dairy prices", he says, "a farmer said to me 'we're going to have to get nitrogen to work more efficiently'".

Williams had already been googling fine particle application and decided to give it a go himself, mixing up some urea in a blender in his kitchen until it looked like "a kid's slushy", then spraying it on his lawn next to a patch treated with granular urea.

"The difference in grass growth was phenomenal."

The big challenge was finding the equipment to grind up and apply the fertiliser - he spent about $200,000 developing a machine that could do it.

Then he started some free trials, including spraying 100ha of a farm near Taupo owned by Landcorp's Pāmu Farms.

Williams says the results were impressive, with three times the grass growth of standard urea.

Even taking into account the added cost of spreading the fertiliser in fine particle form, the method works out far cheaper for the farmer, he says.

"Within 16 days, you could graze the paddock again. If they did that with granular [urea] they'd be waiting six to seven weeks. It's bloody amazing."

TOM LEE/STUFF Prilled urea in wetted form and treated with urease inhibitor is applied to a farm in Waikato.

The farm manager, Richard McNae, confirmed the trial "worked really well" but he wasn't authorised to speak to the media.

Williams says he hoped to do the rest of the farm, and others in the area which had shown interest, but reps from the fertiliser companies convinced them not to proceed.

"The fertiliser companies discredited it. They were saying [the result] was because it's such a great growing year. That's bulls....

"The fert companies don't want it because if it really took off farmers would buy a quarter of the amount of urea.

"Environmentally, it's the right thing we should all be doing."

Simon King, Pāmu's head of communications, says the state-owned company is regularly approached by suppliers who use the fine particle method and it's been observed on some farms.

"However, at this stage Pāmu has not been presented with consistent data ... that provides the confidence we need to conclusively use it as a substitute for other application methods for nitrogen fertilisers."

Pāmu is committed to lowering its use of synthetic fertiliser on its more than 120 farms, King says, and will continue to assess the fine particle method.

Williams has given up, and sold his machine to another helicopter operator.

"I'm sick of banging my head against the wall. If they want to keep pouring [granular] urea on their ground, so be it - let them do what they want, not what they should be doing."

Matt Newton, owner of Precision Helicopters in Taranaki, bought Williams' machinery.

He treats about 30,000ha a year, around 15 to 20 farms, using the fine particle application method.

"In a nutshell, it's just a way of distributing the nutrient perfectly evenly and that's where it shines. There's less waste and it's way better for the environment. You can't beat it really."

But, Newton says, even though you only have to use about half the amount of urea, the costs of spreading it are much higher and he thinks for that reason it hasn't taken off like it could have.

"If I've got to do a [fine particle] job I've got to turn up with a fertiliser factory - I'm carting around mixing tanks and quite a bit of complex equipment."

Brett Emeny, the doyen of fine particle application whose company FPA NZ has won environmental awards, says it's been an uphill battle over many years to convince the industry to get on board.

"That's the crazy thing, it's not new to us but it's new to everybody we introduce it to, every new farming group or consultancy firm, Landcorp - they say 'sounds good but we really don't know a lot about it' - then you have to run demonstrations to show them how good it is.

"Tradition has been our biggest competition all the way along."

Emeny says years of trial work shows that fine particle application produces about twice the growth response as granular fertiliser, making it more economic despite the higher costs of spreading.

"The cost per kg of growing the grass is a whole lot lower, that's the beauty of it - so its a high standard of fertiliser application and the end result is a lower cost per kg of grass growth."

He doesn't want to criticise Ballance and Ravensdown because he still has to buy fertiliser from them, but you can sense his frustration when he talks about their reluctance to back the method.

"What they don't like is farmers taking the option of putting lower rates on and getting as good a result - their business is a volume sales business.

"They'll argue until the cows come home that there's not enough science to qualify that there should be a change to this type of technology."

SUPPLIED Dr Jamie Blennerhassett, innovation leader at Ballance Agri-Nutrients, was once a believer in fine particle application of fertiliser. Not now.

Dr Jamie Blennerhassett used to be a believer in fine particle application.

Now, as innovation leader for Ballance, he's a naysayer.

He first became aware of the technology over a decade ago when he was head of research and development for Summit Quinphos, a small fertiliser company that was later bought out by Ballance.

Emeny approached the firm saying "we've got this cool technology, are you interested", Blennerhassett says, "and we said 'yes'."

They did field trials, "and we got results that convinced us enough to start selling and promoting the concept."

But he says further independent trials through AgResearch didn't back up those results.

"Essentially they all came back and showed, yes there was a slight increase in the uptake through the leaves as urea ... but that never ended up resulting in any extra pasture.

"So you got a little boost to begin with and it never flowed through."

Claims the system is better for the environment are overstated, he says, as 90 per cent of leaching comes from cows' urine rather than directly from fertiliser.

Blennerhassett says Ballance is focusing on products containing urease inhibitors which disrupt the chemical process that causes nitrogen to be lost to the atmosphere.

He rejects the argument that the fertiliser companies are holding back new technology to protect volume sales. Ballance sold 1.64m tonnes of product in the past financial year for profit of $71m, up from $57m the year before.

"As a co-op we don't want to sell fertiliser our customers don't need. If you look at the biggest driver of our shareholders at the moment, it's in the environmental space ... they want us to help solve burning sustainability issues."

Ravensdown's chief scientific officer, Dr Ants Roberts, says proponents of fine particle application will often add other things, such as the growth hormone gibberellic acid, which can boost grass growth.

They have to claim huge efficiency gains, he says, to justify the greater costs.

"The claims they make, I can't see being justified by the science, therefore I tell the farmers 'look at the cost, and you'll get no extra benefit of doing it that way'."

A Ravensdown spokesman insisted that sales tonnage is not the key performance metric for the company.

"In those situations where the science showed that the farmer and environment would gain from applying less fertiliser, then that was a win for Ravensdown."

Dr Bert Quin says "establishment" scientists have their "minds in the mud" when it comes to more efficient ways of applying nitrogen fertiliser.

Quin is a highly respected researcher who was chief scientist for soil fertility at the Ruakura Research Centre in the 1980s before setting up his own firm, Quinphos Fertilisers.

Along with Blennerhassett, he was an early advocate of fine particle application but has since developed his own system which he claims is even better.

Called Onesystem, it uses urea in prilled form, negating the need for expensive grinding machinery. A urease inhibitor is applied to the wetted prills as they are spread, which Quin says prevents loss to the atmosphere.

It's been used on a large farm in Victoria, Australia to good effect, he says, but the fertiliser co-ops here "damn it with faint praise".

"There's a simple reason. If you make urea twice as efficient you're only going to sell half as much."

The Ministry of Primary Industries has given more than $16m to fertiliser efficiency projects led by Ballance and Ravensdown but Quin says they focused on things like how to spread fertiliser on hill country.

"We're the only country in the world that's doing virtually no research on how to make fertiliser nutrients themselves more efficient.

"I try not to think about what could really have been achieved with a fraction of the taxpayers' dollars."

Meanwhile, the debate over whether the fine particle application method actually works continues to rage.

An article in the New Zealand Journal of Agricultural Research in May, by ex-AgResearch and Ballance agronomists, reviewed the research on fine particle application and found there is "insufficient evidence to show any agronomic advantage ... over a granular fertiliser product".

But a literature review by agricultural consultant Chris Crossley, commissioned by Living Water, a joint project between Fonterra and the Department of Conservation, found there were significant benefits from the method, with greater pasture growth and reduced nitrate leaching.

Living Water's national manager, Sarah Yarrow, says the group commissioned a fine particle application trial at Waituna, Southland, where slightly more grass growth was achieved with about half the nitrogen used in granular application.

She says although the fertiliser companies have upped their use of sustainability consultants, their volume sales model is an impediment to progress.

"I don't think they've addressed what does it mean if we need to use less fertiliser to achieve the environmental outcomes we want, what does that actually look like?"

Once the Waituna results have been analysed, Yarrow says, Living Water will approach the companies about what more needs to be done to convince them fine particle application is viable.

"If I was a farmer making choices about buying half as much fertiliser and one of the benefits might be that you reduce your impact on the environment, then why wouldn't you? It's kind of a no brainer."

Mark Shepherd, principal scientist of farm systems and environment for AgResearch, says from what he's seen of the Waituna trial, the possibilities are exciting.

"There definitely seemed to be a yield advantage, I definitely think there's something in it."

Shepherd says he's been impressed with the trial work done by FPA NZ, which builds up its database every time it takes on a new client, and he has spoken to Living Water about doing a full analysis of the data.

Shane Harold worked in senior roles for Ravensdown for 26 years before starting his own firm, Fert Wholesale Direct.

KAVINDA HERATH/STUFF Shane Harold of Fert Wholesale Direct with ammonium sulphate fertiliser from China.

He promotes Quin's Onesystem and is scathing of the lack of efficiency gains in the use of fertiliser in the past 30 years.

There's a simple reason for it, he says - the duopoly control of the industry.

"In a nutshell, having no competition stifles innovation. They [the big two companies] are reliant on 1970s and 80s science, they are not investing in a lot of what I call productive science.

"Because New Zealand doesn't have direct competition it has allowed the industry to price products to allow them to maximise tonnage rather than perhaps benefit [the environment]."

Harold claims that during his time, sales reps were trained to dissuade farmers from trying alternatives.

A contract milker from Taupō, who asked that his name not be published for fear of repercussions, says he saw first hand the "outstanding" results of a fine particle application trial on his farm.

But fertiliser company reps convinced the owner the system wouldn't work.

"It's an uphill battle for a lot of us managers. Farm owners are fairly traditionalist - they do everything by the book and do as these fert companies tell them to do.

"The fert companies are in it for the money obviously - they have a lot of influence over the farmers."