Family: Fabaceae

Senna italica (Port Royal senna, Senegal senna) is a legume tree native to Africa, Asia and the Middle East. It is commonly cultivated as a laxative, along with the species Cassia senna. The laxative is produced from the leaves of the plant, and frequently consumed in the form of a tea. It is reported to be naturalized in the Caribbean and Venezuela but is not documented to be naturalized on any Hawaiian Islands to date. Although it is cultivated for medicinal or ornamental purposes, caution is advised due to the potential for side effects. Senna italica may exhibit invasive traits due to rapid growth, prolific seed production, efficient seed dispersal mechanisms, and adaptability to various conditions. Its ability to thrive in diverse habitats, coupled with disturbance tolerance and allelopathic effects, contributes to its potential invasiveness.

High Risk Traits:

• Broad climate suitability and environmental versatility
  
• Grows and spreads in tropical climates
  
• Naturalized in the Caribbean and Venezuela (no evidence in the Hawaiian Islands)
  
• A weed of pastures, disturbed areas, waterways, and wastelands (and reported to displace native species in these habitats)
  
• Other Senna species are invasive
  
• Potentially allelopathic
  
• Conflicting reports on unpalatability to browsing animals
  
• May possess toxic properties
  
• Tolerates many soil types (unlikely to be substrate limited)
  
• Reproduces by seeds
  
• Fast growth rate, and reaches maturity in <1 year
  
• Seeds dispersed internally by animals, water and intentionally by people
  
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire

Low Risk Traits:

• Unarmed (no spines, thorns, or burrs)
  
• Thrives in disturbed, high light environments (dense shade my limit spread)
  
• Not reported to spread vegetatively