Family: Salicaceae

Origin, Description & Uses
Oncoba spinosa (snuff box tree) is a small to medium-sized tree native to tropical and southern Africa as well as the southwestern Arabian Peninsula. It is known for its distinctive white, fragrant flowers with prominent yellow stamens and its unusual woody, spherical fruits that resemble small “snuff boxes,” which is where its common name comes from. The tree typically grows in dry woodland and savanna habitats and is valued in its native range as an ornamental plant. It is sometimes used in traditional medicine, and its hard wood and striking flowers also make it of interest for horticultural and landscape use in warm, dry climates.

Risks & Threats
Oncoba spinosa is considered low risk and is not known to be invasive or naturalized in Hawaiʻi. It does not show strong traits associated with aggressive spread, such as prolific seed dispersal over long distances or rapid colonization of disturbed ecosystems. While it may be cultivated ornamentally in suitable climates, there is currently no evidence that it poses a threat to native Hawaiian ecosystems. As with any introduced plant, continued monitoring is recommended, but at this time it is not considered a concern for ecological harm in the Hawaiian Islands.

High Risk Traits:

• Thrives in tropical climates
  
• Elevation range exceeds 1000 m
  
• Cultivation escape in New Zealand
  
• Spiny
  
• Tolerates many soil types
  
• Can from thickets
  
• Spreads vegetatively by suckering
  
• Seeds spread by mammals (possibly pigs in Hawaiian Islands)
  
• Can resprout from roots if cut or damaged

Low Risk Traits:

• No reports of invasiveness or negative impacts outside native range
  
• Medicinal and ornamental uses, and used as a barrier plant
  
• Seeds not documented to be bird-dispersed