Family: Pittosporaceae

Origin, Description & Uses
Pittosporum viridiflorum (cape cheesewood) is a small to medium-sized evergreen tree native to tropical and southern Africa, Madagascar, and the southwestern Arabian Peninsula. It has glossy green leaves, clusters of fragrant greenish to yellow flowers, and orange seed capsules that split open to reveal brightly colored sticky seeds. Cape cheesewood is valued as an ornamental tree for hedges, windbreaks, and landscaping because of its dense foliage, attractive form, and tolerance of a range of growing conditions. It has also been planted in some regions for shade, screening, and habitat restoration projects.

Risks & Threats
Cape cheesewood is naturalized on Oʻahu, Lānaʻi, Maui, and Hawaiʻi Island. This species possesses traits that are cause for concern, including the ability to spread beyond cultivation and establish in disturbed and natural areas. Its bird-dispersed sticky seeds can aid its movement into forests and other sensitive habitats, where it may compete with native vegetation and alter ecosystem structure. Because tropical island ecosystems are especially vulnerable to invasive plants, the continued spread of Pittosporum viridiflorum could negatively impact native biodiversity and ecosystem health. For these reasons, choosing a low-risk or native alternative is recommended whenever suitable alternatives are available.

High Risk Traits:

• Naturalized outside native range (e.g., O'ahu, Lana'i, Maui, and Hawai'i)
  
• Congeneric weed (P. undulatum is highly invasive)
  
• Shade tolerant
  
• Tolerates wide range of soil conditions
  
• Produces viable seed
  
• Dispersed intentionally by people
  
• Dispersed by water, birds, and other animals (sticky seeds)
  
• Seeds survive gut passage

Low Risk Traits:

• No spines, thorns, or burrs
  
• Not allelopathic or parasitic
  
• Not toxic to animals or humans
  
• No vegetative spread
  
• No persistent seed bank (no dormancy)
  
• Not wind-dispersed