Family: Rutaceae

Origin, Description & Uses
Triphasia trifolia, commonly known as limeberry, is a dense, thorny evergreen shrub native to tropical Asia, with a natural range extending from Bangladesh to Papuasia. It produces glossy, dark green, trifoliate leaves, fragrant white citrus-like flowers, and small, bright red berries that are edible and mildly sweet. Because of its attractive foliage, fragrant blooms, and tolerance of pruning, limeberry has been widely cultivated as an ornamental hedge, barrier planting, bonsai specimen, and edible landscape plant. It is also valued for its fruit and as a rootstock for some citrus species.

Risks & Threats
Triphasia trifolia is naturalized on Oʻahu and possesses traits that are cause for concern in Hawaiʻi. Birds and other animals readily disperse its abundant fruits, allowing new plants to establish far from cultivated areas. Its dense, thorny growth can form persistent thickets that compete with native vegetation, hinder forest regeneration, and reduce habitat quality in tropical island ecosystems. Once established, these thorny thickets can be difficult to remove. Because of these invasive characteristics, planting limeberry is not recommended where low-risk or native alternatives are available. In areas where the species is already widespread, existing plants should be carefully managed and its use avoided in or near natural areas and regions where it is not yet widely established to help minimize further spread and ecological impacts.

High Risk Traits:

• Naturalized outside native range (USVI, Florida, Texas, Puerto Rico, O'ahu)
  
• Invasive environmental weed (Florida, Barbados, Puerto Rico)
  
• Forms dense, shading thickets
  
• Produces sharp spines
  
• Host for Asian citrus psyllid (vector of citrus greening disease)
  
• Tolerates wide range of soils and shade
  
• Intentionally spread by people (hedge plant)
  
• Bird-dispersed seeds
  
• Seeds survive bird gut passage

Low Risk Traits:

• No vegetative spread (no bulbs, tubers, or fragmentation)
  
• No known toxicity (berries edible)
  
• Not a climbing/smothering vine
  
• Not prolific seed producer