Family: Boraginaceae
High Risk Traits:
- Broad climate suitability
- Naturalized outside native range (but no evidence from Hawaiian Islands to date)
- A weed of gardens, landscaping, and crops
- A potential environmental weed in Australia
- Other Symphytum species are invasive
- Toxic to animals and people if consumed in large quantities
- Tolerates many soil types
- Reproduces by seeds
- Hybridizes with other species
- Reaches maturity in one growing season
- Seeds dispersed by water, ants, and intentionally by people
- Able to be dispersed by tillage that moves plant parts
- Tolerates and grows back from repeated cutting
Low Risk Traits:
- Native to regions with temperate to Mediterranean climates (may only be a threat in higher elevation tropical regions)
- Unarmed (no spines, thorns, or burrs)
- Provides fodder for livestock (palatable despite reports of toxicity)
- Not reported to naturally spread vegetatively
- Self-incompatible
- Primarily bumblebee pollinated (may limit seed production)
- Limited seed production
- Transient seed bank
- Herbicides may provide effective control