Family: Myrtaceae

Origin, Description & Uses
Syzygium australe (brush cherry) is an evergreen tree native to eastern Australia. It is valued as an ornamental landscape plant for its dense, glossy green foliage, attractive white flowers, and colorful pink to red fruits. Brush cherry is commonly used as a hedge, screen, topiary specimen, or small shade tree because it responds well to pruning and can form a compact, attractive canopy. The fruits are edible and may be eaten fresh or used in jams and preserves, adding to its appeal in home gardens and urban landscapes.

Risks & Threats
Although Syzygium australe is not currently known to be naturalized in the Hawaiian Islands, it possesses traits that are cause for concern. The species produces abundant fleshy fruits that can be dispersed by birds and other animals, potentially allowing it to spread beyond cultivation. In regions outside its native range, related Syzygium species have demonstrated the ability to establish in natural areas, where they may compete with native vegetation for light, space, and resources. Because tropical island ecosystems are especially vulnerable to invasive plants, the introduction and spread of species with these characteristics could negatively affect native habitats and biodiversity. For these reasons, choosing a low-risk or native alternative is recommended whenever suitable options are available.

High Risk Traits:

• Naturalized beyond native range
  
• Environmental weed in New Zealand and Australia
  
• Congeneric (Syzygium jambos) is a serious invasive weed
  
• Shade tolerant at some life stages
  
• Tolerates a wide range of soil conditions
  
• Produces viable seed
  
• Propagules dispersed unintentionally (soil movement)
  
• Propagules dispersed intentionally by people
  
• Propagules water dispersed
  
• Propagules bird dispersed
  
• Propagules survive passage through the gut
  
• Tolerates mutilation and resprouts from cut stumps

Low Risk Traits:

• No spines, thorns, or burrs
  
• No evidence of toxicity to animals or humans
  
• No prolific seed production (>1000/m²)
  
• Propagules not adapted to wind dispersal
  
• No external animal dispersal mechanism
  
• Fruits edible (not toxic to humans)