Phragmites

Even with limited distribution, Phragmites can outcompete native plants in locations where it takes hold.

Place of origin

Originally from Eurasia, it is unclear how this subspecies of phragmites (Phragmites australis australis) was introduced to Canada. It was found in 2 locations in Alberta near Brooks in March of 2016 and has since been sighted in various other isolated locations.

Habitat

Grows in shallow water, up to 1 meter near the shore of still or slow-moving water, such as that found in wetlands or ditches.

Identification

  • Perennial with large stems up to 4 m tall.
  • Alternating leaves, 25 to 50 cm long and 1 to 5 cm wide.
  • Feathery seed head with several flowered spikelets that are 10 to 18 mm long.
  • Identification is complicated by a native counterpart found in Alberta, Phragmites australis americanus. Due to similar appearance, DNA analysis is required to confirm species.

Issues

  • Phragmites australis australis is highly competitive and forms dense stands, outcompeting native plants for water and nutrients.

Current management in Alberta

Both stands of phragmites found in Alberta were treated in 2016. The terrestrial stand was treated with herbicides, while the stand in water was cut and burned.

Control of phragmites can be difficult, especially once well established. Methods for control or eradication by trained personnel include a combination of cutting and/or burning, as well as chemical treatment.

Resources

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