Bayer announces Roundup alternative with rollout of new weedkiller in Australia
ABC Rural Brandon Long 7/10/25
The global agrochemical company behind the controversial weedkiller glyphosate has unveiled plans to introduce a new class of herbicide in Australia.
Bayer says the product, icafolin-methyl, is the first new chemical specifically designed to kill sprouted weeds by attacking leaves to hit the market in more than three decades.
The company has submitted applications for the product to regulators in the European Union, the United States, Canada and Brazil, and will seek Australian approval next year, with a rollout expected in 2028.
Farmers battling herbicide resistance welcome the move, but environmental groups are not convinced the full risk is understood.
Cost of resistance
Since its introduction in Australia in 1974, glyphosate, the key ingredient in Roundup, has become a critical tool in food production.
But growing resistance, both from the weeds it fights and some consumers, has impacted its effectiveness, with few good options to replace it.
Bayer Crop Science Australia and New Zealand managing director Warren Inwood said the new chemical would complement, not replace, glyphosate.
“The holy grail in research and development in herbicide activity is trying to find something to replace Roundup or glyphosate, which is as safe as glyphosate,”
Mr Inwood said.
“Icafolin will become a crucial tool, but it won’t be a direct replacement … we will continue supporting Roundup in our portfolio.”
Both glyphosate and icafolin are non-selective herbicides that kill all plants they contact, unlike selective herbicides, which spare desired plants.
Herbicide resistance develops when some weeds survive the repeated use of the same chemical, then reproduce, passing that adaptation on to future generations of the plant, making them harder to kill.
The Grains Research and Development Corporation (GRDC) estimates herbicide resistance costs Australian grain growers $3.3 billion annually.
Mr Inwood said incafolin had shown strong results in Australian trials against some of the country’s most troublesome weeds, including glyphosate-resistant ryegrass.
“Driving productivity in food security is increasingly important and the cost of weed control and management in Australia has increased,” he said.
“It will combat a significant number of resistant weeds, including ryegrass, and other hard-to-control weeds.”
Unlike with glyphosate, the Australian arm said at this stage, it was not targeting the home gardener, local government markets, or use with genetically modified crops.
Balancing the need
On Queensland’s Darling Downs, grain grower Stuart McIntyre said the product could provide much-needed relief in the ongoing fight against weeds.
“It’s always pretty exciting as a grain grower that we’ve got extra arsenal in our weaponry against the constant battle of weeds,”
Mr McIntyre said.
He said glyphosate’s declining effectiveness was evident in his paddocks.
“I’ve been farming 13 or 14 years and in that short time I’ve noticed going from a fairly low dose of Roundup killing spear thistle to now having to use other herbicides along with glyphosate to knock it down,” he said.
“To use something else again would be of great benefit.”
But not everyone is convinced.
Environmental group Friends of the Earth Australia raised concerns about the potential rollout.
Land use researcher Anthony Amis said more information was needed on the long-term impact of exposure to frequent low doses.
“In typical fashion this new pesticide will probably gain regulatory approval without scientists having all available information,”
he said.
“[There are] no details regarding the ecological impacts of this chemical, particularly its impacts on birds, bees and aquatic life … spray drift and water contamination.”
The chemical will need to be registered for use by the Australian Pesticides and Veterinary Medicines Authority (APVMA), which regulates which chemicals can be sold in the country, and how they are used.
The APVMA said when reviewing a chemical, it takes in a wide range of scientific data submitted in support of an application.
“On occasion, credible new scientific information may be generated after a product has been registered that suggests the existence of previously unknown risks to human health, animal or crop safety, the environment or trade, or that suggests product ineffectiveness,” it said.
“If this happens, we can initiate a reconsideration process to assess the identified risk and determine whether changes are needed to ensure that the product can continue to be used safely and effectively.”
Bayer said it would submit a “robust dossier” to APVMA, including local trial data on residues, efficacy and crop safety.