Family: Euphorbiaceae

Origin, Description & Uses
Joannesia princeps, commonly known as arara nut-tree or anda-açu, is a large, fast-growing tropical tree native to eastern South America, particularly Brazil’s Atlantic Forest region. It can reach impressive heights and is valued for its broad canopy, smooth gray bark, and large, lobed leaves that give it an ornamental presence in landscapes. The tree produces sizable, woody fruits containing oil-rich seeds. Historically, these seeds have been used to produce oil for soap-making, illumination, and other industrial purposes, though they are not edible. Due to its rapid growth and attractive form, it is sometimes planted as a shade or reforestation tree in tropical regions.

Risks & Threats
This species is considered low risk in Hawaiʻi and other tropical areas where it is cultivated. It has not shown significant invasive tendencies, and there is little evidence of it spreading aggressively beyond planted areas. While the large fruits may create some litter beneath the tree, and the seeds contain toxic compounds that should not be ingested, these factors pose minimal ecological concern. Overall, Joannesia princeps is not known to significantly impact native ecosystems, making it a relatively safe choice for planting when managed appropriately.

High Risk Traits:

• Broad tropical climate suitability
  
• Repeated introductions outside native range
  
• Toxic to humans (seeds cause vomiting, diarrhea)
  
• Shade tolerant
  
• Tolerates wide range of soils
  
• Produces viable seed
  
• Dispersed intentionally by people

Low Risk Traits:

• No naturalization recorded
  
• No weedy races or congeneric weeds
  
• No spines, thorns, or burrs
  
• Not allelopathic
  
• No vegetative reproduction
  
• No wind, bird, or external animal dispersal
  
• No prolific seed production