"What we are doing right now, may not be appropriate in the future" is Will Russell's advice when it comes to fertilising dairy pasture.
Mr Russell's family property at Jellat Jellat near Bega, NSW, is part of a dairy nutrient management trial investigating the most effective way to fertilise dairy farm pastures without adding excess nutrients.
"The prudent thing to do is soil test, if not every year every second year, so you are not to continually mining those basal elements," said Mr Russell, who milks 350 head.
The main focus of the research is to demonstrate how to convert the highest proportion of nitrogen fertiliser into pasture growth, while ensuring the least amount is lost into nearby waterways.
He said it was important research as farmers could waste a lot of money putting fertiliser on and not getting the results with potential run-off because of the rainfall (800 millimetres a year).
Mr Russell said his property was a suitable site as it has a pivot that is kikuyu-based with ryegrasses and oats over-sown.
"The Local Land Services (LLS) wanted to trial different forms of nitrogen and basal element to see if that made a difference," Mr Russell said.
"We were interested to see if the techniques and management of our current fertiliser program, we were using at the time was suitable."
His program is 80 kilograms of urea every second grazing, which changes throughout the year, where it could be every 40 days to every three months over winter.
He tends to run 150kg of nitrogen a hectare each year, which converts to 350kg of urea a hectare.
'We thought that was a sustainable level. We do know that others in the industry use a lot more than that on dairy pasture," he said.
"Before the trial we were worried by just putting urea on we were missing out on other elements ... from the results it seems like for now we are on the mark."
"We put that down to the fact the paddocks the trial has been done in is a grazing paddock and night time paddock for cows.
"So when they graze there they spend more time getting other nutrients through urine and cow manure that is being put back on the pasture."
The research was conducted by the NSW Department of Primary Industries' (NSW DPI) Clean Coastal Catchments (CCC) Research project, in collaboration with South East LLS, and showcases the benefits of soil testing and better fertiliser management to cut farm costs and reduce potential nutrient pollution in coastal creeks, rivers and estuaries.
NSW DPI soil chemistry researcher Dr Simon Clarendon said samples were collected regularly from the trial site to show which fertiliser treatments reduce nutrient loss while maintaining growth.
"Results from this sampling also demonstrate to our participating farmers how data gained from soil testing can help optimise fertiliser use to maximise pasture production and minimise the risk of nutrient loss," Dr Clarendon said.
Samples from water leaching through the paddock are also tested and analysed to determine how much nitrogen can be lost through inefficient fertiliser management.
CCC research and development officer Luke Jewell said if farmers applied excess nitrogen, it could flow off farm into sensitive ecosystems such as marine estuaries, where algal blooms and fish kills could cause both economic and environmental damage.
The CCC research project and LLS were working with growers to keep sediment and nutrients on farms and out of coastal waterways while supporting profitable and sustainable agriculture.
The 10-year strategy was developed by the NSW Marine Estate Management Authority to co-ordinate the management of the marine estate.
