Family: Pinaceae

High Risk Traits:

• Widely naturalized
  
• Temperate tree with a broad elevation range
  
• Environmental weed in the USA, Australia and New Zealand
  
• Flammable and increases fire risks
  
• Shade-tolerant
  
• Tolerates many soil conditions (and potentially able to exploit many different habitat types)
  
• Can form dense thickets
  
• Hybridizes with other Pinus species
  
• Periodically produces large seed crops
  
• Seeds may persist in the soil
  
• P. nigra is among the least susceptible to herbicides
  
• Tolerates low intensity fires

Low Risk Traits:

• Temperate tree could probably only be grown at higher elevations of tropical countries
  
• Palatable to grazing animals (could prevent spread)
  
• Non-toxic
  
• Not self-fertile
  
• Long time to reproductive maturity (15+ years)
  
• Landscaping and ornamental value (Christmas tree)