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Phragmites Management

Controlling Invasive Phragmites

Phragmites australis is an invasive plant species present in London, and is considered to be the worst invasive plant in Canada. The City of London is an identified leader among other municipalities and levels of government in demonstrating a proactive approach to the management of invasive species in our Parks, Woodlands and Environmentally Significant Areas (ESA's) since 2006. The City has been managing invasive Phragmites in ESAs since 2013 in partnership with the Upper Thames River Conservation Authority (UTRCA). These efforts will be expanded under the London Phragmites Management Strategy (LMPS), a City-wide Phragmites management document to be completed in early 2018.

Help Prevent the Spread of Phragmites

  • Report a Phragmites sighting.
  • Learn to identify Phragmites to avoid accidental spread through plant fragments or seeds.
  • Never buy or plant invasive Phragmites. See Ontario Invasive Plant Council’s Grow Me Instead guide.
  • Do not compost Phragmites, contact your local Environmental Depot to properly dispose of plant matter.
  • Inspect and clean clothing, pets, maintenance equipment and vehicles when leaving an area that you suspect contains Phragmites.
  • Refer to Ontario’s Invasive Phragmites - Best Management Practices for more information on preventing the spread of Phragmites.

Frequently Asked Questions

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  • What is Phragmites?

    Exotic, invasive Phragmites australis, also known as Common Reed, is a tall wetland grass considered to be the worst invasive plant in Canada, and is present in London, Ontario.

  • How does Phragmites spread?

    Phragmites can spread through seed dispersal (from seed heads), rhizomes (roots), stolons (above ground runners) and stem dispersal. Wind and water can assist in the transportation of plant material to new areas, however humans are the main cause of spread. Contaminated heavy equipment, all-terrain vehicles, clothing and pets can cause spread, as well as planting Phragmites as an ornamental. Once plants become established, growth is exponential through stolons and rhizome growth.

  • How might Phragmites impact London residents?

    Phragmites can pose a safery risk to humans from “Phragmites fires” and reduced roadway sightlines. It can also negatively impact drainage infrastructure, agricultural land, property values and recreational activities.

  • How does Phragmites impact the environment?

    Phragmites also has negative implications on our natural heritage system. Due to its rapid reproduction, Phragmites can easily outcompete native species, decreasing biodiversity and displacing habitat for Species at Risk, specifically in wetlands.

  • How can Phragmites be identified?

    Phragmites can be identified by its tall, thick stands up to 5 metres in height, often seen in wet areas such as roadside ditches and marshes. Invasive Phragmites has beige or tan stems with blue-green leaves which differ from the appearance of the native Phragmites subspecies, that has reddish-brown stems, yellow-green leaves, smaller seed heads and is far less common.

  • What is the City of London doing to control Phragmites?

    Phragmites control is already underway in London’s Environmentally Significant Areas (ESA) in partnership with the Upper Thames River Conservation Authority (UTRCA) since 2013. Additionally, the City has collaborated with the Ontario Invasive Plant Council (OIPC) to develop the London Invasive Plant Management Strategy (LIPMS) in 2017, following the OPIC’s strategic municipal framework. Phragmites is identified as a "priority species" in LIPMS. Subsequently, the City has retained Dr. Janice Gilbert, Wetland Ecologist and leading Phragmites expert in Ontario, to assist with the London Phragmites Working Group (LPWG) in developing a City-wide London Phragmites Management Strategy (LPMS). This strategy aims to expand current control efforts of Phragmites through community partnerships and long-term goals.

  • What are the control measures for Phragmites?

    The most effective control measure for Phragmites is the use of herbicide application in combination with other non-chemical methods (ex. mowing). These control methods are coupled with long-term monitoring of controlled sites and re-treatment as necessary. Due to the extensive underground root system, digging or pulling by hand is not an effective measure of control.

  • How will herbicides be applied?

    Chemical control of Phragmites involves targeted, specific herbicide spray application. Herbicides are approved for use by Health Canada, and carefully applied by licensed applicators following the Best Management Practices approved by the Ontario Invasive Plant Council and the Ontario Ministry of Natural Resources and Forestry. These Best Management Practices consider the presence of native species including Species at Risk, and the surrounding landscape features through effective application, timing and concentration of herbicide.

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