MANY more farmers are taking up a natural approach, writes LYNDAL READING
Integrated pest management expert Dr Paul Horne is encouraging broadacre croppers to put away the boom spray.
Dr Horne has worked with dozens of grain growers in Victoria for the past few years, teaching them the principles of IPM.
Dr Horne said often it was a pest management crisis that was the catalyst for farmers taking up IPM.
"In Victoria, we were able to demonstrate that the farmers could get control over a whole range of pests," Dr Horne said.
"They experimented for a year or two and then adopted IPM."
Dr Horne said the biggest obstacle was overcoming farmers' concerns about the risk of IPM.
"It depends on having an IPM adviser," he said.
Dr Horne said insecticides were used as support tools, instead of as a primary tool.
"Previously, spraying insecticides was routine - people would put it on, just in case," he said.
"That attitude has changed entirely."
Dr Horne said that, in broadacre cropping, there were predatory mites that would eat lucerne fleas and beetles that would eat slugs.
He said those predators occurred naturally, so the key was to stop killing them.
"Farmers need to stop spraying and allow the naturally occurring insects to build up," he said.
Dr Horne said the full IPM program included bio-control, time of planting, selection of varieties, selective use of herbicides, baiting and seed dressing.
He said while pesticides had worked well for decades, farmers using IPM were reaping the benefits of lower chemical costs and helping to avoid secondary pests and resistance.
Dr Horne said working closely with growers through agronomists, farming systems groups and other advisers, providing hands-on assistance with implementation and providing working examples of IPM on their own farms, had resulted in more than 50 growers using IPM.
"Fifty might not seem like a lot, but there were no growers doing it only a few years ago," he said.
Dr Horne said some farmers he had worked with hadn't used insecticides through a boom spray in five years.
Inverleigh farmer Rowan Peel said it had been years since he had used insecticide in a boom spray on a paddock.
He said his move to IPM came several years ago when he was battling a slug infestation.
"We spent $20,000 in one year on slug bait," Mr Peel said.
He started working with Dr Horne to work out about beneficial insects.
"Paul found out what our major problems were," Mr Peel said.
"He understood that if we had to spray, then that was okay."
Mr Peel said his attitude had changed from spraying insecticides twice, as a matter of course, to using seed dressings and he had cut his chemical use significantly as a result.
He said it was important for farmers starting out with IPM to be committed to the process.
"I had a red-legged earth mite infestation and I wanted to spray it, but Paul told me to wait until the end of the week, so I did," Mr Peel said.
"When I did another count, the numbers had dropped by half because the numbers of beneficial insects had increased.
"It just took them a bit of time to respond."
