In doing so, Dardanup milk producer, Michael Twomey now has robust irrigation data to demonstrate a responsible use of natural resources – something he said is vital in maintaining the dairy industry’s ‘social licence’ to operate.
Michael now uses deeper soil moisture probes to inform irrigation timing and system forecasts as a guide for the volume of water to apply to his homegrown feed. These tools help him maintain the soil moisture in the readily available water (RAW) zone for plants to ensure maximum irrigation efficiency.
“With the probes up to 400 millimetres deep, we were able to monitor and maintain the RAW in the soil – which meant we basically started watering a lot earlier than we did historically because we were keeping the RAW available to the plant,” he says.
Michael adopted this technology and practices following three seasons as an ‘optimisation trial site’ for the second phase of the six-year Smarter Irrigation for Profit (SIP) research project, which provided invaluable insights for Australian farmers around effective irrigation.
The Smarter Irrigation for Profit – Phase 2 project (also known as SIP2) was a partnership between the dairy, cotton, horticulture, rice and grain sectors. It was funded by each of the industries involved with support from the Australian Government Department of Agriculture, Fisheries and Forestry as part of its Rural R&D for Profit program.
The research is helping farmers across Australia make better irrigation decisions, which can improve water use efficiency and lead to greater profit.
Looking ahead, Michael will continue to use the soil moisture probes and combine them with his existing soil moisture technology to indicate soil RAW to advise irrigation scheduling.
The SWAN system will also continue to be used to advise irrigation volumes.
“It’s quite a good guide,” Michael said.
“Sam Taylor (agronomist and optimisation site coordinator) compared it against the weather data, and it came out pretty good.
“It would be even better if we could also get rainfall and evaporation data after the fact too. That would make irrigation scheduling even more accurate.”
The SIP2 project found increased water productivity was gained by implementing key irrigation principles:
- Maintaining irrigation systems will ensure efficient and effective operation.
- Determining Readily Available Water (RAW) for each soil type being irrigated.
- Using a water balance calculator tool to inform irrigation scheduling decisions – applying water at the right time and right rate
- Monitoring forecast evapotranspiration (EVo) and rainfall to assist in more immediate decisions.
- Monitoring soil moisture using professionally installed soil moisture monitors and reliable telemetry to inform irrigation start-up decisions or after rainfall events.
- Commencing irrigation on-time at the beginning of the season or after rainfall to avoid a green drought scenario where future irrigation is ineffective.
- Knowing the capacity of the system and scheduling irrigation to maintain soil moisture requirements whilst deploying other cost-effective measures (e.g. off-peak power).
- Maintaining soil moisture within the RAW zone to create the ideal platform for strategic nitrogen use.
To read more about Michael’s irrigation journey, visit optimising-homegrown-feed-at-dardanup-wa.pdf (dairyaustralia.com.au)
Dairy Australia is supporting dairy farmers with using effective irrigation systems to increase farm productivity and profitability, drive water-use efficiencies and reduce input costs.
To find out more about irrigation system maintenance and checklists to get you started, visit Irrigation System Check | Dairy Australia
