Family: Salicaceae

Origin, Description & Uses
Salix matsudana (Chinese willow, globe willow, tortured willow, or Peking willow) is native to China and other parts of East Asia. It is a fast-growing deciduous tree known for its graceful, often contorted or “twisted” branching form, especially in ornamental cultivars such as ‘Tortuosa.’ It typically thrives in moist soils and along waterways, producing narrow, elongated leaves and a broad canopy. This species is widely planted as an ornamental shade tree and is also used for windbreaks, erosion control, and in some regions for basketry and other small woodcraft uses due to its flexible branches.

Risks & Threats
Although Salix matsudana is not currently known to be naturalized in the Hawaiian Islands, it possesses traits that are cause for concern. Like many willows, it grows rapidly, reproduces readily from broken branches, and can establish in wet or riparian habitats where fragments can root easily. These characteristics raise the potential for spread along streams and wetlands, where it could compete with native vegetation, alter streambank structure, and increase water consumption in already limited freshwater systems. Because of these potential impacts, caution is recommended, and ongoing evaluation is needed to determine whether this species could negatively affect Hawaii’s ecosystems if introduced or more widely planted.

High Risk Traits:

• Naturalized in Australia, New Zealand, mainland North America and elsewhere (but no evidence in the Hawaiian Islands to date)
  
• Designated as an environmental weed in Australia and New Zealand, impacting native biodiversity
  
• Other Salix species are invasive
  
• Tolerates many soil types
  
• Reported to form dense stands in New Zealand
  
• Hybridizes with other Salix species
  
• Reproduces by seeds and spreads vegetatively by stem fragments
  
• Seeds dispersed by wind and intentionally by people
  
• Spread vegetatively by water and discarded garden waste
  
• Tolerates repeated pruning and cutting

Low Risk Traits:

• Primarily a temperate species; may limit ability to spread to upper elevations of tropical climates
  
• Unarmed (no spines, thorns, or burrs)
  
• Dioecious (requires male and female trees to produce seeds)
  
• Seeds lose viability quickly (will not form a persistent seed bank)
  
• Herbicides may provide effective control if needed