Family: Euphorbiaceae

Cnidoscolus aconitifolius subsp. aconitifolius, commonly known as tree spinach or chaya, is a fast-growing shrub or small tree native to southern Mexico and Central America. It has large, deeply lobed green leaves and a woody, upright form that can reach 10 feet or more. Chaya is best known as a nutritious leafy vegetable; its cooked leaves are rich in protein, vitamins, and minerals and are widely used in traditional dishes and home gardens. Because it tolerates heat, drought, and poor soils, chaya is often planted as an edible hedge, food-security crop, or ornamental foliage plant in tropical regions.

Unlike other members of the genus, this subspecies is currently rated Low Risk. While chaya does have traits such as rapid growth and easy propagation that warrant mindful management, there is no strong evidence that C. aconitifoliussubsp.aconitifolius poses a significant threat to Hawaiʻi’s natural ecosystems at this time. Health-related risks remain, as the raw leaves and sap contain toxic compounds and must be cooked before consumption. With responsible cultivation and proper handling, this subspecies can be grown safely with minimal ecological concern.

High Risk Traits:

• Broad climate adaptability (tropical/subtropical)
  
• Can naturalize in non-native areas
  
• Spreads vegetatively through cuttings and fragmentation
  
• Tolerates and benefits from pruning or damage
  
• Tolerates a wide range of soils and some shade
  
• Dispersed intentionally by people and unintentionally via garden debris

Low Risk Traits:

• Domesticated forms rarely produce viable seeds
  
• No reported weediness in agriculture, forestry, or natural areas
  
• Non-climbing; does not form dense thickets
  
• Not toxic to animals when properly prepared
  
• Many cultivars lack stinging hairs
  
• Not allelopathic, parasitic, or a fire hazard
  
• No persistent seed bank
  
• No natural mechanisms for long-distance dispersal (wind, water, animals)