Phragmites

Description	Invasive phragmites	Native phragmites
Latin name	Phragmites australis subsp. australis	Phragmites australis subsp. americanus
Look	Dull, tan or beige stems Blue-green leaves that are darker than the native variety Large, dense seed heads	Shiny, reddish-brown stems Yellow-green leaves Smaller, sparser seed heads
Growth	Grows in stands that can be extremely dense with as many as 200 stems per square metre Stands include both live stems and standing dead stems	Grows in stands that are usually not as dense as the invasive plant Frequently mixed with other plant species
Density	Is so dense that it crowds out other species	Other species have enough light and space to grow in same area
Height	Up to 6 metres	Up to 2 metres
Common locations	Roadside ditches (very common) Wetlands Agricultural lands	Unlikely to be found in roadside ditches Commonly interspersed with other plant species
Leaf sheaths	Dead leaf sheaths stay on stem	Dead leaf sheaths are loose and drop off easily in the winter, leaving bare stems standing in the spring
Stems	Stems break down very slowly, forming a dense thatch	Stems break down quickly

 

• Crowds out native vegetation resulting in lower plant diversity
• Provides poor habitat and food for local wildlife
• Growth can impact local water levels and drainage infrastructure
• Increase fire risk as stands are composed of dry dead stalks
• Causes increased risk to road safety due to reduced sightlines
• Interferes with agricultural crop growth

 

1. Do not purposely plant it.
   Invasive phragmites is available at garden and horticultural centers. Learn to identify the difference between invasive and native species or select other native grasses for gardening.
2. Avoid the spread of seeds to new sites.
   When leaving an area containing phragmites, brush off clothing and clean equipment.
3. Do not compost invasive phragmites.
   The seeds and rhizomes (root system) can survive and start growing in compost. Cut plants can be left in place to decompose.

 

Methods used to control phragmites vary based on specific site characteristics. A combination of a non-chemical method (mowing or cutting) followed by a specific herbicide spray application applied by licensed applicators is one of the most effective ways to control phragmites. However, herbicide application may be prohibited in areas close to water and best management practice guidelines must be followed. Spot herbicide application over a 3-5 year period may be required to completely eliminate phragmites growth in targeted areas.

Control methods that don't work

• Cutting without use of hebicides
• Cutting or treating only some of the phragrmites grouping
• Cutting the plants afer a sead head develops
• Using a lower concentration of herbicide, applying at the wrong time, or not under proper weather conditions
• Cutting before or too soon after treatments

Control methods that do work

Please visit the Government of Ontario website for additional information on best management practices for phragmites.

 

Oxford County is working with stakeholders to develop a long-term strategy to tackle invasive phragmites. You may see County employees and County Contractors along roadways cutting and spraying the weed, starting in May-June, 2019

There may be opportunities for residents to partner with the County and participate in the Phragmites control plan.  If you think you have invasive phragmites on your property and would like more information please contact Oxford County Public Works at 519-539-9800 or publicworks@oxfordcounty.ca.

 

• Ontario Invasive Plant Council
• Ontario Invading Species Awareness Program
• Government of Ontario - Invasive species in Ontario