Canberra wineries are appealing to local farmers not to let the poisonous spray they use drift from their properties across to vines.
The wine producers have detected the herbicide 2,4-D on their crops, and say the chemical threatens to cause serious damage to an important industry.
The destructive herbicide on vines comes just as the industry is swinging into its autumn harvest season. Vines (and tomato plants) are particularly sensitive to the herbicide.
"It can travel for kilometres and it's hitting our vineyards," grape-grower Jennifer Fischer, President of the Viticultural Society of the Canberra District, said.
Yass Valley Council is warning farmers that it is illegal to allow the chemical to drift away from the property on which it is being used.
The grape growers and wine-makers suspect the chemical is being used by unidentified farmers to control thistles. The farmers are killing weeds which harm their own crops but - unwittingly or not - also damaging the crops of others.
"What we are concerned about is the long-term future of our vines," Ken Helm, one of the pioneers of the wine industry in Canberra region, said.
"We want to work with the farmers," the founder of Helm Wines 50 years ago said.
He suggests that farmers who are planning to spray should get in touch with the Viticultural Society or with council Biosecurity Officers on 02 6226 1477. There are alternative chemicals available, he said.
Yass Valley Council is promoting a course in May on responsible spraying.
The spray drift problem comes at the end of a tough five years for the industry in the Canberra wine-making region. It follows the fires and the resulting blighting of crops by smoke. A bad hail storm then destroyed crops on January 6, 2022.
There was a late spring frost last year which destroyed some of the buds on vines so that the yield was hit. Jennifer Fisher reckoned that this year's harvest would be down by about a third. "We're getting very low tonnages," she said.
"The last five years have been very tough," Ken Helm said. "Business can't get hit year after year and still survive.
"The industry is very important to Canberra and to the Yass Valley."
Mr Helm said that there was some concern about spray drift from households as well as from the wine industry.
"There's a fear out there," he said. Local people reasoned that if the herbicide was going onto vines, it would also be going onto roofs and, from there, into water tanks.
But he emphasised that the industry wanted to work with farmers to get cooperation and neighbourly thoughtfulness.
