Family: Poaceae

High Risk Traits:

• Broad climate tolerance (USDA zones 7–11; heat, cold, drought, salt, fire)
  
• Naturalized in Australia, New Zealand, South Africa, Europe
  
• Agricultural weed (unpalatable, reduces pasture & livestock carrying capacity)
  
• Environmental weed (forms dense stands, threatens native grasslands)
  
• Congeneric with serious weeds (e.g., N. trichotoma)
  
• Sharp seeds injure livestock, cause blindness, contaminate wool
  
• Unpalatable to grazing animals
  
• Creates fire hazard in dry ecosystems
  
• Forms dense thickets / pure stands
  
• Produces abundant, viable seed
  
• Fast maturity (flowers in first year)
  
• Persistent seed bank (>1 year)
  
• Tolerates fire & mutilation (resprouts; fire enhances seeding)
  
• Dispersed by wind, water, machinery, soil, clothing, footwear, animals
  
• Popular ornamental → intentional human dispersal
  
• Seeds attach externally to animals & survive gut passage

Low Risk Traits:

• No toxicity to animals or humans
  
• Not a host for major crop pests/pathogens
  
• Not shade tolerant
  
• Not a vine, aquatic, nitrogen-fixing, or geophyte
  
• No vegetative fragmentation (reproduces only by seed)
  
• No bird dispersal (birds eat seeds as predators)
  
• Controllable with herbicides (e.g., glyphosate, Gallant)