Early harvesting of grain, at high moisture, followed by drying and/or aeration cooling is common in wetter parts of the world and a meeting of grains industry representatives in Tamworth has debated the system’s likely performance in Australia. 

Present were a grower with 20 years experience of high moisture harvesting, two consultant agronomists, a harvest contractor, a buyer for a major feed company, a maltster, the local business manager of a header manufacturer and a couple of scientists specialising in grain storage.

The meeting was called to obtain early industry input to three years of Grains Research and Development Corporation (GRDC) supported research into the potential of early harvesting of high moisture grain to improve yield, quality, cost efficiency and risk management in the Australian crop.

The project draws on the national network of grain storage specialists that collaborated on earlier GRDC projects looking to improve the use of phosphine and the potential of high flow aeration to dry or cool grain in storage and better maintain grain quality after harvest.

The northern region component of the project is led by the Queensland Department of Primary Industries and Fisheries (QDPI&F) but will involve input from Primary Industries and Resources South Australia, the University of South Australia, Agriculture Western Australia and the Victorian DPI.

New South Wales project co-ordinator, consultant John Cameron, says research in Western Australia and in Queensland points to significant losses in grain quality and yield for every day lost after physiological maturity.

“More generally we know that, on average, about 10 per cent of Australian grain crops are downgraded every year because of weather damage, depending on variety, location and time,” Mr Cameron said.

“Much previous research on the potential of early harvesting in Australia relied on hot air driers to manage high moisture grain, and industry adoption was limited by the high capital and variable costs involved.

In some market segments there was also buyer dislike for grain that had been treated at high temperatures that can affect grain quality

“Now relatively low-cost aeration, which allows moist grain to be stored for later drying with high flow rates or air at, or close to, ambient temperature, provides a more cost effective option to match harvest capacity that does not rely on high temperatures for drying.

It lets the Australian grains industry take a fresh look at early harvesting.

“This GRDC project recognises that the whole grain industry value chain has to be involved if its findings are to be widely adopted on farm and for early harvested grain to win market acceptance by continuing to deliver the specific qualities required.” 

Mr Cameron said while the Tamworth meeting generally accepted that early harvesting at high moisture had many advantages, including better utilisation of expensive harvesting machinery and preservation of yield and grain quality, there were also constraints to its widespread industry adoption. 

Some end users might worry about specific quality problems with “green” grain while on-farm concerns could include the capacity of headers to handle high moisture crops and uneven crop maturity across paddocks.