Invasive Phragmites

Invasive phragmites (Common reed) –Phragmites austrilis

Photo by Stacy Schumacher

Invasive Phragmites

Where did phragmites come from?

  • Invasive phragmites is native to Europe
  • Invasive European strains were likely introduced during the 1800’s in ship ballast water

What does phragmites look like?

  • Invasive phragmites is a tall, perennial grass that can grow 15 feet or more in height
  • Stems are light tan in color and hallow
  • Leaves are blue green in color, flat and wide
  • Flower heads are dense, fluffy, and gray or purple in color

Why is phragmites a problem?

  • Invasive phragmites is a fast-growing plant that forms dense stands that consume available growing space and push out native plants that are vital to birds, fish, and wildlife
  • Invasive phragmites degrades wetland and wildlife habitats with dense growth, thus reducing critical resources for birds and other wildlife
  • Dense stands impede the movement of boaters, fish, and wildlife
  • Large populations alter hydrology, dry up wetlands, impede water movement, and increase the potential of fire risks

How does phragmites spread?

  • Phragmites is spread predominantly through seed dispersal – seeds are dispersed from November through January and each seed head can produce up to 2,000 seeds
  • Phragmites can spread to new areas when fragments break off a parent plant and are moved to a new location where they can root. This can happen through natural events such as wind and water
  • Humans can also unintentionally disperse seeds via contaminated equipment, gear, or boats
  • Invasive phragmites are attracted to disturbed areas, open spaces that are free of competitors can easily be colonized

How do we control phragmites?

  • Well-established stands invasive phragmites are difficult to control
  • Herbicide treatments containing glyphosate and imazapyr can be used to control and reduce large populations
  • Herbicide treatments in conjunction with prescribed fire, mechanical pulling or cutting, and flooding can be used to control phragmites
  • Treatments usually need to be repeated annually to control dense stands
  • Thoroughly inspect equipment, gear, and boats for loose vegetation and remove
  • Never take fish or plants from one lake and put them into another

LINKS:

https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspx?SpeciesID=2937

https://www.greatlakesphragmites.net/files/LS-FactSheet-1.pdf