Steve Shirtcliffe at an AHRI talk last month discussed the future of herbicide resistance and weed control

Professor Steve Shirtcliffe, from the University of Saskatchewan in Canada, laughed when his colleague took a rotary hoe into his office as a suggestion for weed management.

However, with weeds becoming more resistant to herbicides by the year, it is evident that either pesticide development needs to rapidly accelerate in speed (but with increasing regulations for testing, this seems unlikely) or farmers need to innovate with weed management techniques.

At an Australian Herbicide Resistance Initiative talk earlier this month, professor Shirtcliffe described Western Australia as the "Disneyland of herbicide resistance," as it appeared that most weeds had multiple resistances - and the list of resistant weeds was growing by the year.

There is no shortage of innovative ideas out there, the problem is finding one that is economically viable.

Professor Shirtcliffe believed the answer was in manipulating agronomy to get better weed control - either through seeding rates or machines such as the rotary hoe.

In his recent studies, he found that increasing the seeding rate would decrease the amount of weeds that grew, as they had less space to grow.

To win the war against weeds, the secret is to keep weeds down early on.

As soon as asymmetric competition begins, where the weeds are getting more sunlight and shading the crop, it is basically game over.

Sometimes this critical period can be a matter of days.

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Professor Shirtcliffe said the rotary hoe had been adopted by the organic community to reduce weeds, but not so much by conventional farmers.

"I think it's because herbicides are still working mostly and they don't need to do it," he said.

"They don't need another piece of equipment - even though we've established that when it's used properly there are excellent results."

Timing is important when using a form of mechanical weed control - whether that's through a rotary hoe or tilling - as it has to be while weeds are still young.

Professor Shirtcliffe experimented with mechanical weed control that entered about 20-30 centimetres into the ground, which dislodged weeds but not the crop.

"Most of our weed seeds emerge from a very shallow depth, and crops are usually anchored by then," he said.

He believed the "tall poppy syndrome" and a slow adoption curve were the main reasons farmers weren't switching to mechanical solutions.

"It's just human nature that people don't want to do something different," professor Shirtcliffe said.

"Everybody drives by and when you do something different everybody sees, and if it fails you look like a fool

"You've lived in this community your entire life, with your parents, your grandparents, your great grandparents, so there's a lot of pressure to not to be the tall poppy in that situation."