Why is it a problem?
- Spreads laterally by rhizomes and root fragments
- Spreads by seeds (up to 30,000 per plant) that remain viable up to 10 years, and are spread by wind, water, and insects
- Aggressively forms persistent, dense stands that outcompete native plants, particularly for soil moisture
- Unpalatable and toxic to grazing animals
- Host for the tobacco mosaic virus
- Establishes in disturbed places and can spread to adjacent undisturbed sites
- Listed as noxious in Alaska and many other states and territories
How do I manage this plant?
- Clean boots and equipment before leaving an area with an infestation
- Cut, mow, or till before seeds mature to prevent seed production and germination
- Follow-up treatments are needed for 10 years to eliminate seed bank
- Reseed with native grasses to increase competition
- Herbicides are effective