Invasives Blog

The fight to control invasive phragmites – one of the worst invasive plants in Canada due to its impact on wetlands, waterways and natural areas – has been highlighted in a new video by CABI partners Ducks Unlimited Canada.

Invasive phragmites threatens biodiversity by eliminating native species, including a native phragmites; destroys wetland habitats; and adds extensively to the maintenance costs of infrastructure. These dense stands make wildlife movement difficult and provide poor habitat and food supply for wildlife.

CABI is playing a key role as part of a team of international scientists – that includes those from Ducks Unlimited Canada and the University of Toronto – who have spent 25 years researching effective biological control agents to fight invasive phragmites.

European moths show promise in attacking phragmites

Two European moths – Archanara neurica and Lenisa geminipuncta – are currently establishing themselves and are showing promise in attacking invasive phragmites following the release last year of over 17,000 insects at 13 sites in southern Ontario.

The research team, that includes scientists from CABI’s centre in Switzerland and colleagues from Canada, focused on an intensive laboratory rearing programme for the caterpillars and on testing release methods using insect eggs, caterpillars, pupae and adult moths.

In the new video, which is available to see on Ducks Unlimited Canada’s YouTube channel, Matt Bolding, Ontario Invasive Species Program Lead at Ducks Unlimited Canada, Dr Ian Jones, Post Doctoral Researcher, University of Toronto, and Dr Rob Bourchier, Research Scientist at Agriculture & Agri-Food Canada, outline how Archanara neurica and Lenisa geminipuncta are being used to control phragmites.

Invasive phragmites were introduced into North America from Europe in the 1800s. Without any natural predators, the plant gradually spread and has become all too common a sight along highways and waterways.

The Canadian Food Inspection Agency (CFIA) approved the release of the biological control agents in Canada in 2019 after extensive safety testing confirmed that they are highly specific to invasive phragmites – meaning that they can only complete their lifecycle on this plant.

The caterpillars of the two moths feed inside the invasive phragmites stems, causing the weed to wilt or die. The released insect populations have survived over a year at the release points and are causing visible damage to phragmites plants at several release locations.

Additional information

Main image: Invasive phragmites is one of Canada’s worst weeds (Credit: ©Harry Rose (Macleay Grass Man)/via Flickr – CC BY 2.0).

Video

See the video ‘Biological Control for Invasive Phragmites’ produced by Ducks Unlimited Canada.

Project page

Find out more about how CABI is protecting North America’s wetlands from common reed from the project page here.

Relevant stories

‘A quarter century of research into natural enemies to fight invasive phragmites shows early promise.’

‘Phragmites biocontrol in Ontario.’