The public are being urged to steer clear of two rapidly-spreading invasive plant sites at Hart Road and Jimmy Lee Creek, where water celery and Vietnamese parsley have taken over.
Biosecurity Officer at Tasman District Council, Lindsay Barber, says this year’s mild winter has led to a huge rate of growth and spread. “In the next few weeks, millions of seeds will be released, so we need to destroy the spread along streams and stormwater drains quickly.”
The edible weeds will be getting sprayed with a herbicide that is approved for use over water from Monday 14 December, so the public are advised not to touch or pick them at all.
The weeds could have an adverse effect on both waterways and the environment. Water celery has the potential to block channels and increase sediment, as well as hindering the growth of native plants.
“The invasiveness of these weeds can reduce the habitat quality for insects and fish in our waterways, which is another big concern,” says David Stephenson, Team Leader at the council’s Stormwater and Waste Management department.
It’s thought a spraying programme early next year will help to ease the problem.