The machine works on the effects of urine patches left by dairy cows while grazing. Cows stand still to pee, and the deposit has high concentrations that ultimately turn to ammonia and eventually nitrates that end up in watercourses.
Spikey, the winner of the 2017 Arthur Mead Environmental award from the Auckland branch of Engineering NZ, is available as a 2.8m trailed or 8m tractor mounted unit, designed to operate at 8 - 15km/h depending on terrain.
Ideally used within 48 hours of cows leaving the paddock, the unit’s spiked rotating discs act as sensors to detect urine patches left by the cows while they grazed. An onboard spray system sprays the urine concentrations with NitroStop to slow the conversion into nitrate, allowing more time to convert nitrate into dry matter.
NitroStop works by modifying the processes in the soil that transform the urea in the urine to nitrates; it slows the conversion of soil-bound ammonium into soluble nitrate while at the same time increasing the rate of pasture growth, so nitrogen uptake is increased. Applying the product to urine patches makes for less leaching in prone soils.
Additionally, and at the same time as pasture treatment, an optional precision fertiliser spreader can be used to accurately spread urea prills or granules to rates as low as 10kg/ha, allowing farmers to move away from the more traditional method of high rate applications for maintenance in favour of much lower rates that will result in lower costs and reduced leaching.
Geoff Bates, managing director of Pastoral Robotics, says the Spikey machine fills a hole left by the withdrawal of the nitrification inhibitor DCD that was being detected in milk samples.
“Nitrate leaching is [among] the biggest environmental challenges facing the dairy industry in NZ. Spikey and NitroStop can now fill that gap,” says Bates.
Trials suggest that a farmer using the machine with NitroStop could raise yield by 15%, and that combining the operation with low-dose precision urea prills could push that increase to 23%, he says.
