Family: Equisetaceae

High Risk Traits:

• Broad climate suitability, and elevation range exceeds 1000 m
  
• Naturalized
  
• Weedy and difficult to remove
  
• A serious agricultural weed
  
• Related Equisetum species have become invasive
  
• Toxic to cattle and other grazing animals
  
• Tolerates many soil types
  
• Forms dense stands that may exclude other vegetation
  
• May hybridize with other Equisetum species
  
• Spread by spores and vegetatively by rhizomes
  
• Can resprout if only aboveground vegetative material is removed

Low Risk Traits:

• Thrives mainly in temperate climates, so may only threaten higher elevation ecosystems in the tropics
  
• Unarmed (no spines, thorns, or burrs)
  
• Short-lived spores
  
• Herbicides may provide effective control