Fire warning in cereal hay crops

The Australian Fodder Industry Association (AFIA) said this week that with so many cereal crops being cut for hay in WA there is potential for the increased risk of hay fires.

In 2007-08 the Eastern States experienced over 400 hay fires throughout New South Wales, Victoria and South Australia.

NSW Industry and Investment district agronomist Neil Griffiths said these fires mainly occurred in drought stressed cereal crops.

"We found that the increased sugar levels in the moisture stressed crops provided an ideal environment for higher bacterial activity in the plant," Mr Griffiths said.

"As a consequence heat in the bale increased to the point of spontaneous combustion."

Brookton hay producers Colin and Anna Butcher have noticed the change in crop conditions this year.

"There is so much sugar and sap in the stems of the crop it is gumming up on the cutter bar of the mower," Ms Butcher said.

"When baling, the material is too dry and chaffy so baling is limited to night time.

"This season is a once in a lifetime experience, let's hope it remains that way. The consolation is that the hay is of exceptional quality, with good colour and smell."

What is unique about cutting cereal crops for hay instead of harvesting for grain is the overnight shift in grain growers becoming hay producers.

"The skills in curing hay and knowing when it is ready to be baled is a skill acquired over many seasons and should not be taken lightly," Mr Griffiths said.

"It is not just a matter of rattling the leaves to tell when a windrow is cured."

There are agronomic practices that can reduce the risk of hay fires when dealing with drought stressed crops.

p Heads should be fully emerged from the boot before cutting.

p Crops should be conditioned. Many contractors have mower conditioners. Where headers are cutting the crop, conditioning the windrow must occur soon afterwards.

p Smash nodes of the stem with a hammer on a bullbar. If there is residual moisture the crop is not ready to bale.

p Preservatives and inoculants can help reduce the risk.

p Moisture probes should be used as a guide only.

p Baler mounted moisture meters will help identify suspect bales.

p Monitor bales post baling and when hay is stored for at least eight weeks after baling.

AFIA's Nick McClelland said that many of its members in the Eastern States have had experience with baling drought stressed cereal crops.

"Hopefully the lessons learnt the hard way in 2007/2008 will be avoided in WA," Mr McClelland said.

"While baling hay for many grain growers is a way of recovering costs, it is truly devastating to lose that revenue source when you need it most, to a fire which in many instances could have been prevented with a little knowledge and understanding."

Despite the ongoing threat of spontaneous combustion in hay around Australia, AFIA has not been able to garner support for research on the subject.

Hay fires are thought to be more prevalent when a particular combination of plant sugars, moisture, microbes and heat is present.

"Hay producers need quantifiable guidelines to follow to avoid this costly problem for agriculture," Mr McClelland said.