More than just herbicide

27 Feb, 2013 03:00 AM

AUSTRALIAN farmers will have to adapt to utilising more than just herbicide in terms of weed management if they are to avoid dangerous weed resistance.

A researcher with the Australian Herbicide Resistance Initiative (AHRI), Michael Walsh, has thrown up the example of harvest weed seed control systems (HWSCSs) as a method of driving down weed populations without relying on herbicides.

Dr Walsh said the problem of herbicide resistant weed populations globally was particularly severe in production systems where herbicide dependence resulted in a lack of weed control diversity.

“The dramatic consequences of this can be extreme levels of herbicide resistance in weed populations,” he said.

Dr Walsh said a glaring example of this was in the Western Australian grainbelt where annual ryegrass and wild radish populations were now very difficult to control with herbicides alone.

“Here, as in other regions of the world, herbicide resistance has resulted in a loss of valuable herbicide resources and driven the search for alternate weed control strategies,” he said.

Dr Walsh said it was well known that a key to managing dominant annual weed species was to prevent the input of fresh seed into their short-lived seed banks.

“We are lucky in Australia that our most problematic weeds hold onto their seed at harvest so we have the opportunity to remove or destroy some of these seeds,” he said.

Dr Walsh said a number of HWSC systems, such as the Harrington Seed Destructor, were now being used effectively to target weed seed production in the Australian grain belt.

“Although herbicides remain the number one weed control tool in Australian cropping systems, it is now clear that the inclusion of HWSC systems in weed management programs is enabling weed populations to be driven to very low levels, providing some insurance for the sustainability of remaining herbicide resources,” he said.

“What is absolutely evident is that herbicide sustainability in global cereal production areas will only be achieved if there is diversity in both the agro-ecosystem and in the herbicide and non-herbicide tools employed for weed control.”

Gregor Heard

Gregor Heard

is the national grains writer for Fairfax Agricultural Media
Date: Newest first | Oldest first


27/02/2013 7:12:14 AM

Serrated tussock requires chemical, biological and nuclear warfare to remove it. What does that do to the soil ?
Coota Col
27/02/2013 8:10:35 AM

So in summary growers need to implement an intergrated approach to weed control. Thanks for providing such revolutionary new advice.
27/02/2013 8:26:31 AM

At the risk of being labelled a 'heretic' by some grain growers, in my opinion the strategic use of animals ( particularly sheep) as a method of weed control in many situations. Sheep, with their advanced 'weed seeker' technology can be used successfully in fallow fields to control edible weed species, whilst adding kilos to their live weight at the same time.
27/02/2013 9:42:23 AM

weed control starts with the soil in its Nutrient, Physical & Key biological makeup (all of which can be managed). It's about time we looked at the source rather than the product of current management systems!
27/02/2013 10:29:18 AM

Thats great NSWNoTill but the declaration of war on the live trade has seriously undermined the profitability of all grazing systems. You just wait til the pastoralists north of you get Angus blood into their Brahmans and start flooding you markets with cheap beef. You have been sentenced to a life of cropping, you just don't know it yet. Worse in WA where we don't have a domestic market for our sheep meat. Chemical fallow is taking off with all the debt problems.
27/02/2013 3:48:53 PM

Tillage is just not a economic or sustainable option - sure we can strategically use it to replace 1-2 sprays per year but not for full weed control. Like it or not we need to start working on solutions to the scenario of farming without glyphosate - I don't pretend to have the answers, I don't know who does, but I am sure livestock are likely to be part of the answer as is soil fertility corrections as Gerhard suggests. No easy answers but lets not wait too long to have the debate.
27/02/2013 5:00:20 PM

More to it than just herbicides.......but as Australian farmers continue to be groomed as consumers of inputs and finance, industry focus will remain on selling the remedy, not the solution.
Zero till
27/02/2013 8:36:52 PM

Sheep also destroy soil cover, cause compaction and spread weed seeds. Been over 10 years since we got out of sheep and I don't miss it one bit, as for weeds we are on top of it without animals!
28/02/2013 12:19:02 PM

we were all on top of weeds at one point of time. amazing how you can lose control when the herbicides stop working or seasonal extremes render those strategies less effective.
28/02/2013 3:53:48 PM

look to the soil. it holds the answers. being 'groomed as consumers' as Bosco put it so well, is far from sustainable and not in the interests of farmers and the future of agriculture.


Screen name *
Email address *
Remember me?
Comment *


light grey arrow
Can't you boys find another playground to occupy? Same old punters, same old tired barbs and
light grey arrow
Another of the sacred scare stories comes undone for the agw
light grey arrow
He might well be a decent bloke Chick, however Jock is right on the money regarding Sterles