Family: Cupressaceae

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Grows in temperate to subtropical climates (may only grow at higher elevations in subtropical climates)
  
• Naturalized or naturalizing on West Maui (Hawaii), New Zealand, and possible the Azores
  
• May possess allelopathic properties
  
• Pollen may cause dermatitis or allergies in susceptible individuals
  
• Flammable and may increase fire risk
  
• Shade-tolerant
  
• Tolerates many soil types
  
• Dense planted stands may limit recruitment or regeneration of desirable species
  
• Reproduces by seeds, and possibly by layering
  
• Self-compatible
  
• Seeds dispersed by wind and people (possibly rarely by birds)
  
• Seeds may persist in the soil for at least 1 year
  
• Able to coppice

Low Risk Traits:

• Despite widespread planting, few reports of naturalization, and no documentation of serious negative environmental impacts
  
• Unarmed (no spines, thorns or burrs)
  
• Valued as an ornamental and timber tree
  
• Vegetative spread by layering only in rare circumstances
  
• Reaches maturity in 5-10 years
  
• Herbicides may provide effective control