Family: Asteraceae

High Risk Traits:

• Invasive & spreads rapidly in non-native regions
  
• Forms dense thickets that outcompete native plants
  
• Harmful to agriculture – reduces crop and pasture yields
  
• Toxic to livestock (cattle, goats) and can harm humans
  
• High seed production (up to 800,000 seeds per plant)
  
• Wind-dispersed seeds; also spreads via animals, clothing, machinery
  
• Allelopathic – inhibits growth of other plants
  
• Tolerates disturbance – regrows quickly after fire, cutting, cultivation
  
• Grows in varied soils and drought-tolerant
  
• Reproduces by seed and vegetatively
  
• No effective natural enemies in invaded areas

Low Risk Traits:

• Not bird-dispersed
  
• Limited shade tolerance – prefers open areas
  
• Susceptible to some herbicides
  
• Controlled in native range by natural enemies