It's the single greatest problem facing New Zealand dairy farming - nitrate leaching into lakes, rivers and aquifers - but now there may be a real weapon against it.
Pastoral Robotics co-founder Geoff Bates is wary of claiming a total solution but, in the same breath, he and Bert Quin believe their invention Spikey will cut nitrate leaching in this country by 50 per cent.
The controversy is New Zealand farming's biggest headache. Dairy, traditionally the country's biggest export earner viewed benevolently by New Zealanders, has come in for unprecedented criticism as public and media scrutiny intensifies on damage to waterways from cow urine.
Enter Spikey - so called because of the rows of spiked discs which make contact with the surface soil when Spikey is towed over a farm paddock. The spikes detect recent urine patches with a high degree of accuracy by identifying electrical conductivity changes in the soil after the cows have relieved themselves.
Spikey then treats the urine with an environmentally safe mix of chemicals already widely used in agriculture. One of the components keeps the urea in the urine in this form for a vital few extra days, enabling it to move laterally and make each urine patch bigger. So more of the nitrate formed from the urea is used by the grass (a win for the farmer) and less is left to leach into our waterways (a win for the environment).
"Spikey works for the farmer in two ways - first, there has never been an effective way of finding the urine patches before," says Bates. "Second, it promotes grass growth and more grass means more milk - which means more money.
"We estimate it will reduce nitrates leaching by about 50 per cent. That will have a huge impact on our rivers and lakes - and for the farmers, it means they can continue to be in business without having this issue hanging over them; plus they get to make more money."
Bates and Quin are now readying six Spikeys for sale to early adopters. Each unit costs about $40,000. For an average farm of 400 cows, Bates estimates a cost of $6000 per year in chemicals, with labour costs ranging from $15,000-$20,000.
However, the increased pasture grown on every urine patch means Spikey will soon pay for itself. Bates' and Quin's research points to the average dairy farm making a net profit between $15,000-$20,000 annually from extra grass produced.
"On the big farms in Canterbury, the benefits will come very quickly," he says.
"But perhaps the biggest payback for dairy farmers is that ability to continue farming.
Nitrate leaching has been a reality check for the industry. Look at the Rotorua lakes - there's only so much you can do with good management.
"What's needed is a whole new technology which counters the problem and allows you to get on with running your business."
Spikey, which has an 8m "wingspan", is easily attached to a tractor or farm vehicle and can be quickly towed around the paddocks which have accommodated the herd. Because it treats only recent urine patches, only about 5 per cent of the pasture has to be sprayed - a big saving in chemicals.
Apart from development in New Zealand, Pastoral Robotics is also fielding interest from the Irish dairy industry and agricultural research department interested as they look to foster grass-fed milk with its increasing potential to earn a premium. Bates says Spikey also has huge potential in Australia.
"New Zealand is not the only country which has a problem with nitrate leaching," he says.
The company invited investment capital to build the initial run of farm-ready, 8m-wide Spikeys. They sought expressions of interest on December 23 and were delighted to find all investment needs met by December 24.
"That was pretty gratifying," Bates says, "and it gave us the money we needed to develop the first run of six for early adopters."
They are also working on an agricultural robot known as Mini-Me, a smaller, self-propelled version of Spikey which does the same job but without human supervision.
"It is smaller and takes longer but it's a robot - it has nothing else to do," says Bates, pointing out that Mini-Me will also save farmers labour costs. "However, it is still very much in development with Massey University and it won't be ready for some time yet."
Bates and Quin formed Pastoral Robotics after a chance meeting. Bates (who also invented the Dung Buster for cleaning up milking yards, now used by about 30 per cent of dairy farmers) was developing a proposal for the automatic handling of dairy shed waste; Quin was researching a device fitted to cows to treat urine patches automatically - activated by the cow raising its tail.
Out of a shared passion for cleaning up the waterways came Spikey of which Bates says: "It is the farming of the future. It's the first thing you can do for the economy by way of a lot more precision agriculture which addresses local needs."
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