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Is this Canada's worst invasive species?

Simcoe County forester says spread of Phragmites is 'almost beyond control'
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Some people have called Phragmites australis, also known as the common reed, Canada’s worst invasive species.

Growing up to five metres in height, Phragmites forms dense stands that choke out native plants, reduce biodiversity, and pose a threat to wildlife and to tourism — all but blocking shoreline views where it has become established.

It clogs drainage ditches, leading to localized flooding, and the towering grasses have even been known to block sightlines at intersections. In drought conditions, the dried grasses can pose a fire risk.

Introduced to North America from Eurasia, either as a garden ornamental or as a fodder crop, it has escaped from cultivation to spread through ditches, fields, wetlands, beaches and coastal marshes.

Only in the past few years has there been an effort to monitor and control its spread.

“It’s an evolving process. We’re all — from the federal, provincial and on down — trying to react the best we can,” said Graeme Davis, Simcoe County forester, whose department has been tasked with directing the targeted control of Phragmites, under a new Invasive Species Management Practices policy.

At this point, it may be “almost beyond control,” Davis admitted.

As with most serious invasive species, “nobody realizes there’s a problem until there’s a big problem.”

Phragmites australis has no natural predators in North America. It spreads both by seed, produced by the thousands in each seed plume, and by rhizomes, its root system.

Attempting to pull it up only stimulates rhizome growth, at a rate of up to five metres per year. And those rhizomes secrete phytotoxins that suppress the growth of other plants.

It is hard to know just how far the problem has spread.

“There is no overall mapping in Simcoe County to know where we are in this,” Graeme said.

That is an issue in other jurisdictions as well.

“Right now, we don’t have a handle on the pervasiveness (of Phragmites) in the ditches, private property,” said Sarah Campbell, aquatic biologist with the

Nottawasaga Valley Conservation Authority (NVCA).

Instead, the NVCA has been focusing on areas most at risk — primarily the Collingwood-Wasaga Beach shoreline, and the Minesing wetlands.

With financial support from multiple sources, including the former federal Lake Simcoe Southeastern Georgian Bay Clean-up Fund, provincial Land Stewardship and Habitat Restoration Fund, and Great Lakes Guardian Community Fund, and private foundations such as the RBC Blue Water Project, the NVCA has hired a Phragmites co-ordinator each summer and works with local groups, municipalities and condominium associations to undertake monitoring, mapping and control measures.

The NVCA has had success in coastal and water’s edge areas.

“Cutting Phragmites under the water drowns them,” Campbell said. “It’s the best bang for the buck,” especially when the cutting takes place in late summer.

Partnering with volunteers, who remove the cut biomass from the water, and the municipality which disposes of the cuttings, the infestation in the Collingwood area is now about 40 per cent controlled, she said.

But this is just as long as water levels remain high. “If water levels recede, we’re going to have a problem.”

But on land? “We’re not seeing success,“ Campbell said. “Landowners don’t have the tools right now.”

The Ministry of Natural Resources and Forestry (MNRF) Best Practices for Phragmites Control recommends a combination of techniques, including cutting, prescribed burns, flooding, and use of herbicides — not really realistic for the average landowner.

The MNRF warns against simply cutting Phragmites, since mowing may actually stimulate the growth of the rhizomes.

But the NVCA still recommends landowners cut Phragmites — either early and often, or in late August before the plants set seed — to at least prevent additional seeds from being produced and to avoid composting the plant.

If the fight against Phragmites is to succeed, Campbell said, “it has to be a multi-partner effort,” involving citizens, conservation authorities, and every level of government.

One partnership just getting underway this August involves the County of Simcoe and the Town of Innisfil, working to control Phragmites along county and municipal roads.

Last year, Innisfil completed an inventory and GPS mapping of invasive Phragmites, as viewed from the road.

Staff discovered “over 300 locations ranging from a few plants to very large stands,” said Jeremy Nyenhuis, the town’s drainage superintendent.

Starting in August, the town and county will share a contractor, using a herbicide on Phragmites stands on municipal and county property, following the regulations of the provincial Weed Control Act.

It is a three-year project funded by operating budgets, with each partner paying for the application along their own roadways. The county expects to spend about $2,500 in 2018, with Innisfil paying the remainder.

“The town believes that through this proactive program we can prevent the invasive Phragmites from becoming a major problem along Lake Simcoe’s lakefront,” said Nyenhuis, although he admitted it does not address Phragmites on private property.

Application will be by roadside boom spray truck, and, in more sensitive areas, by hand-applicator, but there are no plans to extend the spraying to private properties, even when the plants have spread onto privately-owned lands from a roadside infestation.

And that is an issue.

There is a patchwork of control efforts — by private landowners, condominium groups, not-for-profit and environmental groups, conservation authorities, municipalities, provincial and federal ministries — but no overarching strategy or funding.

In 2016, Conservation Ontario sent a letter to then-premier Kathleen Wynne, asking the province to push for the approval of herbicides already in use in the U.S. to control the aggressive reed, and for a province-wide program to control Phragmites.

The province did classify Phragmites as a “restricted invasive species” in 2016, making it illegal to import, release, breed, grow, buy or sell the plant, and pilot projects at the Long Point and Rondeau coastal wetlands are testing the effectiveness of herbicides.

“The results to-date have been very promising, and it is hoped that research associated with the pilot will help support the registration of a herbicide product in the future,” said Jolanta Kowalski, senior media relations officer with the MNRF.

The ministry is also working with the Ontario Phragmites Working Group, municipalities and organizations to educate the public.

Through a partnership with the Ontario Federation of Anglers and Hunters’ Invasive Species Awareness Program, it funds a Hit Squad of summer students, who assist conservation authorities in their efforts to manage invasive species.

Spencer Leava is a Hit Squad member assigned to the Lake Simcoe Region Conservation Authority (LSRCA), specializing in Phragmites.

“It’s pretty prevalent throughout the watershed,” Leava said, although the LSRCA has only a few infestations, including a patch at Scanlon Creek, that so far are “generally manageable” on its own property through “a bunch of different control measures.”

Control and removal of Phragmites is a long-term effort that can take years.

“There’s no one miracle way,” he noted.

The LSRCA does not have an official Phragmites control program, said Lauren Grzywniak, land management technician, but instead approaches the issue as “part of the invasive species strategy” — a strategy that also addresses other invasives, like garlic mustard and dog-strangling vine.

She suggested that private landowners who find Phragmites on their property look to the MNRF, Ontario Invasive Plant Council and other organizations for information, but she acknowledged they are largely on their own.

“It’s a big, complex problem” that might not be solvable without provincial or even federal action and funding, although “new money coming from the province for programs like this is a difficult sell,” said Davis.

One best practice being introduced is a clean equipment protocol.

Phragmites is easily spread along roadsides and ditches by construction and ditching equipment. The protocol calls for cleaning of all equipment used in areas of Phragmites infestation — including boots — before anything is moved to a new site.

To be effective, not only government roads departments but private contractors will have to embrace the protocol, said Davis, “and there’s a big cost to that.”

In Bradford West Gwillimbury, Director of Community Services Terry Foran said the town is aware of the problem — but most of the Phragmites are on private lands.

The town cuts the reed along its one-metre right-of-way twice a year, but there are no other plans for control at this time.

Town policy is to clean its equipment in areas of Phragmites infestation to avoid spreading the plant.

“Our guys know what it looks like,” Foran said.

But as for dealing with the wider issue and private property, he said, “I have no answers.”

So far, Phragmites are a “minor problem” in the Holland Marsh, said Drainage Superintendent Frank Jonkman Jr.

There are small pockets on some of the new berms along the canals and along the drains — but the biggest stands are, again, on private property, beyond the control of the drainage authority.

“I have had conversations in the past with various ministries about regulating this invasive, however little to no progress has been made,” Jonkman said. “Some of the techniques that have been used only seem to promote growth instead of curbing it.”

The best method seems to be a combination of cutting and treating with herbicides, he said. “Part of the problem, however, is that unless you get it all, including growth on private property, you really aren’t accomplishing much.”

Phragmites in your area? Report the location at invadingspecies.com or ontarioinvasiveplants.ca, or to the Early Detection and Distribution Mapping System at eddmaps.org/ontario.

Watch out for Phragmites look-a-like:

There is a native species of Phragmites that resembles the invasive, but it is less vigorous.

It has a reddish-brown stem, yellow-green leaves, grows to a maximum height of about two metres, and forms stands that are much less dense than Phragmites australis.

It flowers earlier in the year (June and July), and its seed plumes are smaller, sparser and lighter in colour than the invasive, which generally flowers in late July and August.

The Invasive Species Centre has released a report on the economic impact of invasive species. Based on surveys of 95 municipalities and 13 conservation authorities, the annual cost of monitoring, preventing and controlling invasive species totalled $38.8 million in Ontario.

The bulk of that was spent dealing with the impact of the emerald ash borer and the removal of dead ash trees — but Phragmites was in second place.




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