Common Name
Plant Form
Herbs
Considered Invasive?
Yes
Threat Level
High
Additional Info
Notes: This colorful ornamental perennial, introduced from Europe and still sold commercially for use in garden pools, has escaped from gardens and become an invasive noxious weed. It poses a threat to wetlands throughout much of North America, including Arlington and Alexandria, Virginia, as it colonizes in large numbers and competes with native shoreland vegetation.
Method of removal: Pull up by roots