Residents in the shires of Cardinia and Baw Baw, south-east of Melbourne arebeing urged to report infestations of water hyacinth (Eichhornia crassipes) to Agriculture Victoria.
Agriculture Victoria biosecurity officers recently seized eight water hyacinth plants from a stall at the Wantirna Trash and Treasure Market after receiving reports it was being sold by a stallholder.
Leading Biosecurity Officer Kaitlin Wright said water hyacinth is considered one of the world’s worst aquatic species and is a declared State prohibited weed under the Catchment and Land Protection Act 1994, thereforeit is illegal to sell and propagate it.
“The seized plants were sourced from a dam in the south-east region between Pakenham and Warragul.
“The stallholder mistakenly believed water hyacinth are good plants for fish.
“However, research shows it reduces water quality by decreasing dissolved oxygen and sunlight and can actually be harmful to fish,” she said.
Water hyacinth can be identified by its purple flower spikes in summer. Out of flowering season, the plant is still quite distinctive with bulbous stems and bright dark green, smooth glossy leaves and purple feathery roots trail below the plant in the water.
Ms Wright said it can smother waterways and dams by forming thick mats and blocking access to water.
“It spreads quickly, producing thousands of seeds per plant, with a single infestation doubling in size in just two weeks under the right conditions.
“People sometimes sell or buy water hyacinth without knowing it is an invasive weed.
“We commend the recent actions of gardeners across the state, who have identified water hyacinth after buying it or finding it on their property and encourage anyone who has seen or bought water hyacinth to report it to Agriculture Victoria.
“Agriculture Victoria will work with landholders to remove water hyacinth infestations free of charge.
“Please don’t try to control or dispose of the weed yourself. Agriculture Victoria will organise for the safe and secure disposal of plants, at no cost to the landowner,” she said.
