Family: Fabaceae

Acacia dealbata (silver wattle) is a fast-growing, highly invasive tree that can spread rapidly in Hawaiʻi. It reproduces through seeds, root suckers, and resprouting after cutting or fire. Its seeds are long-lived and easily dispersed by birds, ants, water, and possibly wind, allowing it to establish quickly in disturbed areas. The species can form dense thickets that crowd out native plants and alter local ecosystems.

Beyond its aggressive growth, A. dealbata can hybridize with other Acacia species and may affect soil and plant communities through allelopathy. While it has ornamental appeal and is sometimes browsed by animals, its invasiveness and resilience make it a high-risk species. Management requires careful monitoring and active control to prevent it from overtaking native habitats.

High Risk Traits:

• Widely naturalized
  
• High invasive environmental weed
  
• Potentially allelopathic
  
• Thicket-forming
  
• Hybridizes with other Acacia species
  
• Tolerates many soil conditions (and potentially able to exploit many different habitat types)
  
• Self-compatible
  
• Forms root suckers
  
• Seeds dispersed accidentally and by water, birds, ants and possibly wind
  
• Prolific seed production
  
• Forms persistent seed bank
  
• Resprouts after cutting
  
• Tolerates fires

Low Risk Traits:

• Palatable to animals
  
• Ornamental value
  
• Possibly Shade-intolerant
  
• Herbicides provide effective control