Common Name: Invasive Common Reed
Alternate Names: Invasive giant reed, invasive giant reedgrass, invasive Phragmites
Scientific Name: Phragmites australis subspecies australis (Cav.) Trin. ex Steud.
Similar Species: Native common reed - Phragmites australis (Cav.) Trin. ex Steud.
Efforts must be made to prevent seed maturation and dispersal of plants into new areas. Additionally, no illegal transportation, propagation, or sale of this subspecies is allowed. Failure to comply may result in enforcement action by the county or local municipality. Minnesota Noxious Weed Law
There are two varieties of Phragmites australis in Minnesota. The first is the variety native to North America that is not invasive. The second is an introduced variety (subspecies australis - A.K.A. invasive common reed) that has been shown to be very aggressive and is responsible for displacing populations of native common reed throughout the United States, including Minnesota. This semi-aquatic perennial grass species was first introduced to North America in the 1700s or early 1800s along the eastern seaboard. Over the course of the 20th century, it has spread across the entire continent, invading wetlands, lake shores, streambanks and marshy areas. Both the native and invasive varieties look similar and it takes some familiarity to learn the differences between both plants.
Invasive common reed can be found in a variety of aquatic to semi-aquatic habitats throughout the state. This plant is more likely to be found in disturbed sites where soil has been exposed or nutrient inputs are high such as roadsides, gravel pits, developed shorelines, disturbed wetlands and marshes, flooded areas, eroded streambanks, etc.
Invasive common reed spreads to new areas by both seeds and vegetative means. Vegetative dispersal typically occurs through the movement of root fragments along eroded streams or contaminated soils. Seed dispersal occurs through wind, water, animal and human activities. Existing stands spread horizontally by a vast network of underground rhizomes which can grow up to 10 feet in a single growing season. View invasive common reed distribution in Minnesota.
Invasive common reed grows and spreads aggressively by producing high numbers of seeds, an extensive system of rhizomes, and by out-competing native plant species, thus creating large/dense stands with low biological diversity. Currently, a very small percentage of Minnesota's native wetlands exist throughout the state and invasion by this species puts these few highly valuable remaining habitats at great risk.
MDA Noxious Weed Program
County Ag Inspectors