Family: Euphorbiaceae

Origin, Description & Uses:
Euphorbia ingens, commonly known as cactus spurge or candelabra tree, is native to southern Africa. Despite its cactus-like appearance, it is actually a succulent in the spurge family. This striking plant can grow into a tall, tree-like form with multiple upright, branching arms that resemble a candelabra. It is widely used as an ornamental landscape plant in warm climates due to its architectural shape, drought tolerance, and low maintenance needs. It is often planted as a focal specimen in xeriscapes or dry gardens.

Risks & Threats:
On Oʻahu, cactus spurge is naturalized and spreading beyond cultivation. This species possesses traits that are cause for concern, including its ability to reproduce vegetatively and establish in dry, disturbed habitats. Its toxic, milky sap can pose risks to people and animals, causing skin and eye irritation. Additionally, dense growth may crowd out native vegetation and alter local ecosystems. Because it is already naturalized and has the potential to detrimentally impact tropical island ecosystems, it is recommended to avoid planting Euphorbia ingens and instead choose a low-risk or native alternative better suited for Hawaiʻi’s environment.

High Risk Traits:

• Thrives in tropical and sub-tropical climates
  
• Elevation range exceeds 1000 m
  
• Other Euphorbia species are invasive
  
• Spiny
  
• Sap toxic to animals and humans
  
• Tolerates many soil conditions (and potentially able to exploit many different habitat types)
  
• Self-fertile
  
• Seeds dispersed by birds

Low Risk Traits:

• Questionably naturalized
  
• Ornamental and medicinal value
  
• Can be grown in arid areas and requires little water