Full steam ahead for clean weed kill
STEAM technology to control weeds was invented in Australia in 1997 and machines are manufactured in Sydney.
Weedtechnic managing director Jeremy Winer, and inventor of the technology, said the concept began with the Australian Rail Authority in 1920 which used locomotive steam on a heavy sack to kill weeds.
Mr Winer said there had been greater interest nationally in steam since the IARC's classification of glyphosate last year.
He said councils that consider it to be a cost burden are instead incurring a toxin burden and ran the risk of off-target damage and occupational health and safety issues.
Mr Winer said the council closest to eliminating chemical sprays was Leichhardt in New South Wales and it was the first to use steam to treat weeds.
In climates like Melbourne, one council has found it to be more effective than sprays because chemicals were often washed away by frequent rain.
In Perth, the Eastern Metropolitan Region Council is continuing steam trials with local governments. PERTH councils are turning to steam to control weeds, following concerns about the health impacts of chemical sprays.
International Agency for Research on Cancer last year found glyphosate to be “probably carginogenic to humans”.
The chemical was listed by the IARC in the same category as red meat, high temperature frying and some shift work.
The City of South Perth recently ordered a steam machine and the Town of Victoria Park uses steam to treat “no spray” areas where residents have indicated they do want sprays used. The City of Belmont will start a steam trial in September, hiring a machine to determine its effectiveness.
Councils have “no spray registers”, publicly advertise major spraying events and contractors must use signage while spraying.
The City of Fremantle uses a combination of steam and sprays and has found the cost of steam treatment has risen since 1997 when it first introduced chemical-free trials. Since then, labour costs have increased, technology has become sophisticated and the number of roads and paths has grown in the city.
But on April 27 this year Fremantle resolved to accept the cost of its chosen weed controls.
Steam is used to control weeds in “no spray” areas twice each year in the Town of Victoria Park and there is minor use of white oil in street trees and gardens.
The City of Canning has not applied herbicide to its sporting fields in four years, adopting a precision nutrient management program so the turf can out-compete weeds and in the process scorch any weeds before they mature.
City of South Perth Mayor Sue Doherty said steam was a very effective way of managing weeds, including aquatic species.
“The City is looking forward to the use of this steam treatment as a way of reducing weeds; it is innovative and will be a means whereby the use of chemicals can be reduced,” she said.
But the City of Melville’s acting chief executive Steve Cope disagrees, saying sprays were required for effective and efficient control.
“The City of Melville investigated steaming a number of years ago and at the time it did not prove to be viable given the expanse of paved verges, medians, and kerb lines that need to be managed within the City,” Mr Cope said.
The City of Cockburn and the Shire of Serpentine Jarrahdale directed the Gazette to the Australian Pesticides and Veterinary Medicines Authority website that says glyphosate is unlikely to pose a threat, either carginogenic or genotoxic, to humans.
City of Armadale chief executive Ray Tame said if the APVMA determined there was a risk or hazard, the council would immediately cease to use it.
Some councils are shying away from chemical weedkillers.