Family: Fabaceae

Origin, Description & Uses
Vachellia xanthophloea, commonly known as the fever tree, is native to eastern and southern Africa, ranging from northern Somalia to South Africa. It is a fast-growing, medium to large tree best known for its striking smooth yellow-green bark, open spreading canopy, and delicate, feathery foliage. It naturally grows in seasonally wet grasslands, floodplains, and along rivers but also adapts well to cultivated landscapes. The tree produces fragrant, creamy-yellow flower clusters that attract pollinators and is valued as an ornamental shade tree in parks, gardens, and large landscapes. It is also used for erosion control, wildlife habitat, and occasionally for timber, fuelwood, and traditional medicinal purposes in its native range.

Risks & Threats
Vachellia xanthophloea is considered a low-risk species for Hawaii. Although it produces seeds and can reproduce naturally, there is little evidence that it spreads aggressively or invades natural ecosystems where it has been introduced. In Hawaii and other tropical regions, it has not demonstrated the invasive characteristics seen in higher-risk acacia relatives. As with any non-native tree, seedlings should be monitored and managed if they appear outside cultivated areas, but the species is not considered a significant threat to native habitats. When planted in appropriate locations and responsibly maintained, the fever tree is regarded as a suitable choice for ornamental and landscape use.

High Risk Traits:

• Tropical/subtropical native (climate match)
  
• Broad climate tolerance (zones 9b–11)
  
• Has thorns/spines
  
• Forms dense thickets
  
• Nitrogen-fixing (alters soil)
  
• Seeds survive gut passage
  
• Human-introduced (landscape tree)
  
• Tolerates pruning/lopping
  
• Fast-growing (1–1.5 m/yr)
  
• Persistent seed bank
  
• Tolerates varied soils

Low Risk Traits:

• Not naturalized elsewhere
  
• Not a weed elsewhere
  
• Palatable to herbivores (aids control)
  
• Non-toxic to humans/animals
  
• Shade intolerant
  
• Low seed production
  
• Limited dispersal (water, African mammals)
  
• Not wind- or bird-dispersed
  
• No allelopathy known
  
• Not self-compatible