Storms and showers have exacerbated the challenges of winter crop harvest for growers this season, with grain storage specialists now warning particular care is needed to protect the quality of grain going into silos with moderate or high moisture content.
Grain storage specialist Philip Burrill said the first two to four weeks of grain storage were critical and it was imperative growers monitored and managed moisture levels to get it right.
Postharvest grain storage specialist Philip Burrill says the first two to four weeks of grain storage are critical and growers need to monitor and manage moisture levels to get it right.
Mr Burrill, a Queensland Department of Agriculture and Fisheries (DAF) senior development agronomist, has worked on national grains’ storage trials as part of Grains Research and Development Corporation (GRDC) investments for the past decade.
“The unstable weather across much of New South Wales as growers start or are in the middle of harvest has been really testing,” he said.
“I can understand why growers will take crops off early with a higher moisture content than usual, so they suffer less risk of weather damage, but there are important steps needed to protect this grain in storage.”
Mr Burrill said when it came to grain storage, the valuable early preparations steps were:
- Storage hygiene: Make sure storages are clean, get rid of old grain residues, wash out silos if needed and use diatomaceous earth (DE) products (e.g. Dryacide®), ahead of this season’s crop going into storage.
- Segregation and sampling: Talk to key buyers so you know their preferred grain quality segregations for this season. Check grain testing equipment. Keep running samples as you fill each silo. Once tested, you can confidently discuss the quality of the grain in storage with buyers.
- Check maintenance of storage equipment: Silos, augers, aeration fans and grain spray gear.
- Storage records: Number each silo clearly and keep up-to-date notes – grain quality, grain treatments and fumigations. Check grain in storage monthly and identify and record pests found.
Mr Burrill said aeration was one of growers’ best tools when it came to looking after grain in storage.
“Growers need to aim to have the correct aeration equipment that works well for their storage size and grain types and seek good advice,” he said.
“In any season, across any paddock grain moisture content is variable, so aeration of storages allows you to get some moisture uniformity in storage. It will also drive down grain temperatures which preserves quality and reduces your insect pest risk.”
Wet weather has exacerbated the challenges of winter crop harvest for NSW growers this season, with grain storage specialists warning particular care is needed to protect the quality of grain going into silos with moderate or high moisture content.
When it comes to grain moisture levels at harvest he said grain storage practices for winter cereals could be put in to three general categories: grain at safe receival storage moisture levels (eg under 12.5 per cent for wheat); grain at 13-15 per cent moisture levels; and grain above 15 per cent.
“It is vital growers are proactive in the critical first two to four weeks of storage. Key steps to protect grain quality are aeration management, plus regular checks on grain temperature and smell,” Mr Burrill said.
As a general guide:
Aeration for grain harvested at safe moisture levels (at or below receival standard of 12.5 percent):
- First five days: run aerators continuously, around the clock.
- Next seven days: run aerators 9-12 hours per day, mostly the cooler night hours.
- Ongoing: run aerators for roughly 100 hours per month, selecting cool and dry air.
For grain harvested at 13-15 per cent moisture content:
- This grain can be held safely for 2–4 weeks with aerators run continuously.
- Within the 2–4 weeks, aim to blend with dry grain and aerate, or dry grain with drying facilities
- Once grain is at ‘safe moisture levels’, go through the three aeration stages listed above.
For grain harvested at 15.5 per cent or more moisture content:
- Run aerators continuously, around the clock. Grain is at high risk of serious damage with fans off for more then 2-4 hours.
- Check grain twice a day: use a temperature probe and smell grain at the top of the silo.
- Organize to dry grain within 3–5 days. Hot air (gas/diesel) dryer, or aeration grain dryer with high air flows of 15-25 L/s/tonne.
Mr Burrill said in the case of extended wet or very humid weather for more than half a day, turn off aerators. Then immediately restart when dryer conditions return, below 70 per cent relative humidity (RH).
“Growers are well aware of the need to pay close attention to grain moisture levels and understand that wet grain will get ‘hot’ quickly, so regular monitoring and management of this grain in storage is critical,” he said.
“My other tip is to keep good storage records for each silo, it positions you well as an ‘informed seller’ who manages his storages facilities well. Grain buyers soon learn you are a ‘first choice’ producer.
“After spending six months planting and getting the crop agronomy right, growers are now committed to getting grain storage right and a little preparation and planning will add to your bottom line.”
For more information go to: How aeration works – GRDC Update Advice note on the Stored Grain website.