Of the many invasive plant species that are currently ravaging the landscape of the Cataraqui Region, phragmites are becoming the most persistent, most potentially damaging and most difficult to manage.
Cataraqui Conservation has taken the lead in trying to identify the spread of phragmites and, in conjunction with various partner organizations, including lake associations and even individual landowners, has worked in mitigating this spread.
Holly Evans, Cataraqui Conservation’s Coordinator of Watershed Planning, established a phragmites working group in 2024 and enlisted Watershed Conservation Technician Nick Sterling to help lead the program.
“Many partners in the Cataraqui Region Phragmites Management Area working group pledged their support through in-kind contributions to the program, recognizing Phragmites as an issue. My role is to work with everyone who pledged their support for the project to understand where they would be focusing their monitoring efforts and then collecting that data and identifying the parts of the watershed that aren’t being monitored by partners and fill in those gaps to develop one cohesive map throughout the Cataraqui region,” said Nick.
The working group, facilitated by Evans and Sterling, also got funding to provide phragmites removal kits to anyone interested in managing phragmites on their own property.
“They can be borrowed and used by anyone and used for the ‘cut and drown’ method. This is when you have a patch of phragmites growing in a wet area like along a river or lake: you cut the stem at its base beneath the water, getting rid of the stalk and since it’s been severed and is under water, it can no longer get oxygen. We found that it was an effective way to control phragmites,” he said.
So, let’s step back a bit and talk about the plant that is at the centre of all this work. What exactly are phragmites and why are they such a scourge to local ecosystems?
“Phragmites are a type of perennial invasive grass. They came over from Europe and Asia quite a while ago, and then obviously took over and became invasive, which is why we must put such an effort into monitoring them and getting rid of them,” Sterling explained.
“Phragmites like to grow in wetlands which are the hot spots as far as biodiversity goes and if there’s too much of one thing, there’s fewer of other things, meaning biodiversity goes down when Phragmites takes over. In Ontario it’s particularly bad because we know that directly or indirectly, invasive phragmites is affecting about 25 per cent of our species at risk, including plants, animals, birds etc.”
The worst spots in the Cataraqui Region turned out to be in low lying areas near or along roadsides, which is where Sterling and the phragmites management team spent a good portion of last summer exploring the main and arterial roads of the region.
“Most of the patches we found were in disturbed areas, so along roadsides, along transportation corridors including rail lines. It’s a pretty well-known fact that phragmites like to take hold in areas that have been disturbed by construction that’s worked up the soil and maybe brought in soil from elsewhere,” he said.
“And that’s true with a lot of invasive species; the disturbance is the first thing that opens the door for them to come in. If you have a naturally intact ecosystem or habitat, it’s going to be more resilient to invasion. When we create roads or rail lines, we make the surroundings less resilient. And also, when you think of the wind created when a vehicle passes by it kicks up dirt and disturbs a patch that might lead to seeds getting carried off down the road and deposited elsewhere.”
During last year’s work, close to 3,000 kilometres of road were traversed, with 740 separate unique individual populations of phragmites, representing a total of about 523,000 square metres, found throughout the entirety of the Cataraqui Region – essentially everywhere. And according to Sterling most of these populations were what can be categorized as highly dense, which is anything greater than 70 per cent phragmites compared to other, native species.
With funding being approved for the 2025 season, the working group will use the 2024 mapping as a baseline to develop actual phragmites control and management plans for the areas identified, as well as to fill in a few gaps in the map along shorelines and private access roads, which will be aided by various Lake Associations.
“Phragmites management takes a long time, it’s a year after year process that you have to keep up with. It’s not a ‘one and done’ sort of thing. At least for the next few years, we’re hoping to control phragmites and our management plan will help us do that. It summarizes the monitoring efforts and incorporates best management practices from other sources, arriving at what we’re calling the Cataraqui Strategy,” Sterling said, adding that they are hoping to do some roadside herbicidal spraying this year strictly on road allowances with the permission of municipalities and with ample public notification.
“It’s a relatively easy first place for us to start and it can be implemented on a relatively large scale, which is nice. And engaging the public is always important when you’re dealing with invasive species because often, they get spread without people even realizing it. If people become aware of something, they can act to hopefully prevent the spread,” he said.
“Our Aquatic Invasive Species webpage has a phragmites specific place where you can learn more and there will be a link to our survey. If there’s some interested members of the public who know about a patch in their area or close to their home and they want to put it on our radar so we know it’s there, we can maybe include it in future control efforts and help get rid if it, the best way to do that is use the online survey document.”