In a channel near Cobram, G-MW trialled a ‘flowing injection’ method of weed treatment with Flumioxazin.
A flowing injection involves the weed treatment chemical being released at the top of a section of the channel the water will flow down from.
The water is drawn through the treatment zone at a constant flow and then stopped once the chemical nears the end of the treatment zone.
Flumioxazin is a fast working herbicide that has minimal effect on fish life. In diluted form, Flumioxazin has a very low toxicity to humans and mammals, although there is a a short withhold period that needs to be followed.
G-MW also treats weeds by direct injection of chemical into a static body of water, surface-spraying channels, and by dewatering channels and surface spraying the exposed soil.
G-MW weed maintenance technical adviser Danielle Ick said adding flowing injections to these methods would potentially allow G-MW to be far more comprehensive in its treatment of weeds.
“Flowing injections are very beneficial when treating parts of our channel network that are difficult to access,” she said.
“Traditionally, we would need access to almost the full length of the channel bank to spray the weeds, whereas with flowing injections we may simply need access to a regulator.”
The flowing injection using Flumioxazin was the first of its kind.
G-MW has treated more than 230km of channel with Flumioxazin in 2022, up significantly from the 8km of channel it was used on in 2021.
“The results of our extensive weed treatment program are looking promising and we’re hoping that some irrigators will enjoy improved flows when the irrigation season starts because of it,” Ms Ick said.
“We will continue to monitor the sites we have treated in the coming months.”