Family: Solanaceae

Origin, Description & Uses
Solanum mauritianum (bugtree, wild tobacco-tree) is native to southeastern and southern South America, ranging from Brazil to Argentina (Buenos Aires). It is a fast-growing, soft-wooded shrub or small tree that can reach up to 10 meters tall, with large, velvety, gray-green leaves that are strongly aromatic when crushed. The plant produces clusters of soft purple flowers followed by yellowish, tomato-like berries that are readily eaten and dispersed by birds. It has been introduced to many tropical and subtropical regions as an ornamental and sometimes for perceived uses in traditional medicine, hedging, or as a quick-growing pioneer plant in disturbed areas.

Risks & Threats
Solanum mauritianum is naturalized on Oʻahu and exhibits several traits that are cause for concern, including rapid growth, high seed production, and effective bird-mediated dispersal. It can form dense thickets that displace native vegetation and alter habitat structure, particularly in disturbed sites, forest edges, and secondary forests. Its spread poses a risk to tropical island ecosystems by reducing biodiversity and hindering native plant regeneration. Because this species is naturalized and has invasive tendencies, it could detrimentally impact Hawaiian ecosystems if it continues to expand. When available, low-risk or native plant alternatives should be chosen instead. In areas where it is already present but not yet widespread, management and prevention of further planting or spread are recommended to minimize additional ecological impacts.

High Risk Traits:

• Naturalized, serious environmental weed, worst forestry weed in South Africa
  
• Toxic to humans and animals; causes skin/respiratory irritation
  
• Allelopathic (inhibits native seed germination)
  
• Forms dense, shade-tolerant thickets; tolerates varied soils
  
• Prolific seed production (millions/ha/year)
  
• Persistent seed bank (>1 year; 11–16 month half-life)
  
• Bird- and water-dispersed; contaminates produce/grain
  
• Fruits within 1 year; self-compatible
  
• Resprouts vigorously after cutting/fire; fire triggers mass germination

Low Risk Traits:

• No spines, thorns, or burrs
  
• No vegetative reproduction (seed only)
  
• No evidence of intentional human dispersal