Pale yellow water lily is a South African invasive species that was introduced to a local farm dam a few decades ago, and quickly spread to nearby Gunbower Creek.
North Central CMA project manager Amy Russell said pale yellow water lily significantly impacted the creek.
“It rapidly colonises shallow, nutrient-rich waters, resulting in dense infestations that restrict water movement and contribute to silt build-up in the creek,” she said.
“One of the best methods to kill it is by spraying, and we can only do that at certain times of the year.
“Lowering the water level in winter and making it vulnerable to the frost, as has been suggested in the past, will have little impact.”
North Central CMA contracted Goulburn-Murray Water to begin the eight-week spraying campaign in December, once Murray River flows from Hume and Dartmouth dams subsided.
“We’re targeting about 650 hectares of infestation in the creek and key lagoons, mainly between Cohuna and Koondrook weirs, and up to the national channel,” Ms Russell said.
While there was no spraying during the holiday season, efforts were due to ramp up again soon, she said.
“This is an important job and one the community is right behind. It’s a challenging weed to treat, but we will continue to take as many steps forward as we can and assess year-on-year.”
North Central CMA will also target bridal creeper along the banks of Gunbower Creek near the ski run, and an infestation of horehound in the middle of the Gunbower Forest’s Reedy Lagoon horseshoe.
“That area in the middle of Reedy Lagoon is culturally sensitive and an area we’re really focused on protecting,” Ms Russell said.
“We’ll revegetate with native plants once we have removed the horehound to help protect the area.”
