The program actively seeks to extend the uptake and adoption of agricultural innovation validated through Project Catalyst. Growers are supported to implement improved operations on a farm block, gaining greater understanding of practice change in a practical sense, while also learning more about best possible economic efficiencies. Combined, these two programs drive true innovation by working with growers to modify farm management for positive water quality and economic outcomes.
Game Changer trials were implemented during 2013-14 across the three NRM regions of Reef Catchments (Mackay Whitsunday Isaac), North Queensland Dry Tropics, and Terrain Wet Tropics. A total of 67 trials were undertaken.
ABCD best practice
The growers and their support networks use the sugarcane ABCD best practice framework as their guideline. The aim is to change C and D farm practices (poor or potentially degrading and common practices) into A and B (industry endorsed best management to aspirational and innovative practices), with a legacy after the project is completed.
Participating landholders received agronomic advice and planning support to assist them to improve not only the trial sites but also their overall farm management. Improving the agronomy reduces variations across trial sites which is expected to improve the statistical comparison between treatments. If the landholder is happy with the results, it is anticipated this planning support will result in spreading the trialled activity across each farm. Through group extension activities it is also anticipated, once the trials have proven to be economically and environmentally successful, that other growers will adopt the practices following the leadership of the project’s growers.
Promotion of the project has been undertaken at conferences, forums and field days, media (print, radio and television) and via social media channels.
The 67 trials had a range of investigations which included
- Variable rate nutrient application guided by soil mapping within a paddock to determine changes in soil types. This will increase fertiliser use efficiency (including nitrogen) and is expected to lead to reduced nutrient runoff into waterways, without affecting crop yield. In some cases crop yield may increase.
- Using soil mapping, herbicides are applied at a variable rate across a paddock according to soil texture. This approach capitalises on natural benefits of soil type – for example, light textured soils may use lower rates of herbicides than heavier soils. The default practice of using high application rates of herbicides per hectare results in the surplus running off into waterways. The objective of these series of trials is to demonstrate that varying the application rate of herbicides, using soil maps, demonstrates a reduced rate of herbicide per hectare and less runoff. This reduction in rate of fertiliser and herbicide application will result in lower costs over the long-term, and more efficient use of nutrients and chemicals. In order to achieve this, the landholder will need to have soil mapping completed to guide the use of variable rate application. This is something currently being supported and funded under the Reef Programme free of charge for participating growers.
- Using controlled release fertiliser it is expected that an increase in nitrogen use efficiency will be demonstrated, allowing less nitrogen per hectare to be applied for the same average yield. It is also expected that improved consumption of nitrogen may translate into a higher yield using the same current rates of nitrogen application. The benefit to the environment will be less nitrogen runoff.
- A series of trials investigating the variation of fertiliser rates when using soil ameliorants, accounting for their nutrient content and speed of nutrient release. Recycled organic and mill filter press products such as mill mud, mill ash and compost will be used. Trials are expected to demonstrate and quantify the benefits of soil ameliorant placement and associated reduction of fertiliser input. The environmental benefit will be less nutrient runoff, particularly nitrogen.
- A series of trials investigating and demonstrating potential soil health improvement using different strategies of crop husbandry.
- Variable rate nutrient application due to block yield potential guided by age of the crop ratoon. A crop cycle is defined by the time between the replanting of sugarcane. Crop cycles can commonly vary from three years to 10 years. This series of trials aims to demonstrate that reducing fertiliser inputs as the crop ages in the final year of the crop cycle will not alter the yield outcome. It is expected if adopted that this will reduce nitrogen runoff.
- Investigation of low cost alternative irrigation. Sites have been established with drip systems installed under the ground, expected to demonstrate improved water and nutrient use efficiency.
- Investigation into the benefit of irrigation telemetry and automation. It is expected to demonstrate the agronomic and economic advantage of using automated decision support for irrigation scheduling. These types of trials are topical especially those involving various forms of nitrogen.
- In regard to nitrogen, the message is spreading throughout industry that to reduce the volume entering the Great Barrier Reef, volume used per hectare is not as important as timing, placement, and the form of the nitrogen.