Family: Solanaceae

Nicotiana glauca (tree tobacco, wild tobacco) is a shrub or small tree native to Argentina that has become naturalized in warm, dry regions throughout the world. In Hawaiʻi, it was first recorded on Oʻahu between 1864–1865 and is now found on all main islands, especially in open, arid, and disturbed areas from sea level up to about 350 meters. The plant grows quickly, forming dense thickets that outcompete native vegetation. It produces abundant seed and readily re-sprouts after being cut, allowing it to spread and persist even in harsh environments.

Although Nicotiana glauca is considered invasive in Hawaiʻi, it is also an important host plant for the endangered Blackburn’s sphinx moth (Manduca blackburni), a native Hawaiian moth whose larvae feed on plants in the nightshade family. Because of this relationship, the species is only controlled on a limited basis—typically within ecologically sensitive areas and only after surveys confirm the absence of moth eggs or caterpillars. When management is necessary, the most effective method combines cutting the plant near the base and immediately applying a systemic herbicide to prevent regrowth.

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Thrives in tropical climates
  
• Naturalize on Oahu, Lanai, Maui, Kahoolawe, Molokai, and Hawaii (Hawaiian Islands) and widely naturalized elsewhere
  
• Regarded as an environmental weed (but primarily a weed of disturbed sites in Hawaiian Islands)
  
• Toxic to animals and people
  
• Unpalatable to animals
  
• Host of plant pathogens
  
• Tolerates many soil types
  
• Forms dense stands
  
• Reproduces by seeds
  
• Self-compatible
  
• Reaches maturity in 1 year
  
• Seeds dispersed by water, facilitated by wind and animals and intentionally by people
  
• Prolific seed production (>1000/m2)
  
• Resprouts after cutting and fire
  
• No effective natural enemies present in Hawaiian Islands

Low Risk Traits:

• Primarily a weed of disturbed habitats in Hawaiian Islands
  
• Unarmed (no spines, thorns or burrs)
  
• Importance alternate host for the endangered Blackburn’s sphinx moth (Manduca blackburni)
  
• Ornamental uses
  
• Restricted to sunny, high light environments
  
• Not reported to spread vegetatively
  
• Herbicides provide effective control