14 cane growers involved in trials of new farming practices have collectively reduced their use of urea fertiliser by the equivalent of 19 semi-trailer loads as part of a three-year Australian Government program aimed at reducing nitrogen runoff to the Great Barrier Reef.
Nitrogen fertiliser, usually applied as urea, has been identified as a source of dissolved inorganic nitrogen (DIN) that has been linked to outbreaks of the coral-eating Crown-of-Thorns Starfish.
The 14 growers from across the Wet Tropics took part in the Australian Government’s Reef Trust Phase One Reverse Tender Program. The program allocated funding through a competitive tender process, with interested farmers who had not already made changes to their nitrogen use, stepping up to propose and trial different practices to reduce nitrogen inputs.
These ranged from the purchase of new equipment such as GPS precision machinery and specially modified fertiliser boxes, to the use of enhanced efficiency fertilisers and the use of legumes and biological fertilisers to improve soil health.
Joe Marano, Chair of the Wet Tropics Sugar Industry Partnership (WTSIP), said the cane industry is looking at different ways to reduce fertiliser use but they needed to be proven in trials before they would be adopted by the wider industry.
“These growers were contracted to reduce their use of bagged nitrogen by 178 tonnes but the final results showed they exceeded that amount by over 35 per cent, reducing their application of nitrogen fertiliser by 242 tonnes over the three year project,” he said.
“Each individual grower reduced their nitrogen rates by between 20 and 72kg/ha. This is a great achievement and proves that farmers continue to be a great investment for taxpayers’ money because they so often achieve more than expected.”
Mr Marano said the trials undertaken by the growers demonstrated that improved farming systems boosted the crops uptake of nitrogen enabling growers to tailor their use of fertiliser more precisely to reduce application rates.
“Reducing bagged fertiliser rates means growers save money. Collectively these growers saved a total of over $360,000, that’s a big saving,” he said.
Barron Delta cane grower Mark Savina was one of the growers who took part in the project. He said he is very conscious of the impact his farming practices have on the sensitive end-of-catchment environment he operates in and is grateful that the Australian Government is able to support trials of new practices.
“This project made me take a good look at my N rates and after conducting a number of different trials I now know I can get a good crop with lower nitrogen rates, which is a good thing with the current low sugar prices,” he said.
Mr Marano said the success of this pilot program laid the foundations for the subsequent Reef Trust IV Repeated Tenders program, which rolled out in 2017.
“We now have another 41 cane growers engaged in a similar program to trial different ways of reducing nitrogen rates without affecting productivity. This program will run until 2023,” he said.
“WTSIP’s team of extension officers is also available to provide expertise and support to growers in the Wet Tropics who want to explore changing to more sustainable practices and saving money at the same time,” he said.
Cane growers in the Wet Tropics are encouraged to contact their local WTSIP Extension Officer. To find out contact details go to www.wtsip.org.au/team/
Find out more about managing nitrogen on your farm in this short video.