The Department of Environment and Natural Resources (DENR) Weeds Management Branch is currently fighting a battle against the invasive water weed sagittaria on several fronts.

Of the 27 plants sold at Bunnings in Darwin and Palmerston, 12 have not been returned.

And the one plant sold at Katherine Mitre 10 has not been returned.

Regional weed management officer Roni Opden thanked those people who have so far returned sagittaria plants bought at Bunnings, including Durack residents Bill and Desma Coates.

“Bill and Desma were among the first people to contact the Weeds Management Branch on 89994567 after the urgent recall went out in September,” Ms Opden said.

“Their property backs onto Durack Lakes in Palmerston and Territorians should count themselves very lucky that they contacted us as soon as they became aware of the recall.

“Sagittaria plants spread very quickly and that’s why Weeds Management Branch officers will be inspecting the Palmerston lakes system for sagittaria as this is exactly the type of habitat that it thrives in.

“If allowed to establish in the Lakes, sagittaria would affect the Neighbourhood Fishing Program, water quality and may increase mosquito breeding habitat.”

Ms Opden said the emergency response to avoid sagittaria establishment has entered a new phase following the discovery of an historic planting in a Howard Springs backyard.

“Sagittaria is a highly invasive weed that can devastate our natural waterways and wetlands if given a chance to take hold,” Ms Opden said.

“That’s why we have spent the past two weeks inspecting natural waterways within a 2.5km radius of a Howard Springs property where the plant had been living during the past 10 years.

“Weed Management Branch officers will extend their search by conducting property visits in the immediate surrounding areas of the Howard Springs property.

“We ask that residents who are approached by Weeds Management Branch officers to assist us by cooperating with the requests of the officers and allowing us to check your ponds, drainage lines and wet areas where sagittaria may be growing.

“Seventy properties in Howard Springs have been identified that need to be inspected based on their proximity to the sagittaria finding and suitable wetland environments.

“Property owners will not be in trouble if they have been unknowingly growing sagittaria as an ornamental plant but it will be removed by officers.

“Severe infestations can restrict flows in wetlands and natural waterways, adversely affecting biodiversity and impacting on recreational activities.

“Since detection, sagittaria has shown it is well suited to the Top End climate, indicating that it may prove to be highly invasive and difficult to control if allowed to escape into the Territory’s environment.

“Our recommendation to people wanting to buy aquatic plants as part of any landscaping or outdoor renovations is to buy a Taro (Colocasia esculenta) which is the same one we have given to Mr and Mrs Coates today.”

Previously a Class C (not to be introduced into the NT) weed, sagittaria has recently been added to the Class A (to be eradicated) list of weeds in the Northern Territory, and it is illegal to cultivate and/or sell sagittaria in the Northern Territory.

Anyone who has sagittaria or comes across it is urged to contact the Weed Management Branch on 89994567.

Go to www.nt.gov.au/weeds for more information

Media Note – Roni Opden is available for interview on 89994560