Why is it a problem?
- Spreads by above and/or belowground horizontal stems, produces 4-8 new shoots every year, and can resprout from root fragments
- Spreads by seed (number varies by species, ~20-600 per plant)
- Dispersed by wind and wildlife, and on clothing and equipment
- Produces chemicals that inhibit the growth of other species
- May alter soil nutrients and pH
- Forms dense mats, outcompeting native plants, which reduces biodiversity and forage value for grazing animals
- Found along roads, lawns (garden escapee), pastures, meadows, forest edges and clearings; easily establishes in disturbed sites then spreads into adjacent undisturbed areas
- Can hybridize with other native and nonnative hawkweed species
How do I manage this plant?
- Clean clothing and equipment before leaving a contaminated site
- Mowing can prevent seed production, but promotes flowering and vegetative spread
- Cutting and digging are ineffective control methods, as plants will resprout from small root fragments
- Most effective control method is selective herbicide
- Monitor for several years, as plants are likely to re-establish from the seed bank and root fragments