Family: Berberidaceae

Berberis microphylla (syn. Berberis buxifolia), commonly known as the Magellan Barberry, is a woody, evergreen shrub native to southern South America, including regions of Chile and Argentina. It is easily recognized by its small, spiny, holly-like leaves, vibrant yellow flowers, and attractive purple berries. Historically, this tough, cold-hardy plant has been popular in gardens and landscapes, often used for ornamental hedging and as a barrier plant due to its dense, thorny growth. Its edible berries are also sometimes used to make jams.

Despite its ornamental appeal, Berberis microphylla poses ecological risks and is classified as an environmental weed in certain regions, such as the Falkland Islands. Its bird-dispersed seeds allow it to spread from cultivation into natural areas, where its shade tolerance and ability to form dense, spiky thickets enable it to outcompete native vegetation. While it is not considered a major threat in tropical climates, in temperate regions it can alter habitats and reduce biodiversity. Its presence can also create a physical barrier for wildlife and people due to its sharp spines. Management can be difficult once established, though it is noted to be susceptible to herbicides.

High Risk Traits:

• Environmental versatility: wide soil and climate tolerance
  
• Weed status: naturalized, environmental weed, congeneric weeds
  
• Defensive traits: spines, shade tolerant, forms thickets
  
• Tolerates mutilation or fire
  
• Reproductive: produces viable seeds, self-compatible
  
• Dispersal: intentionally planted, bird-dispersed, survives gut passage

Low Risk Traits:

• Not naturalized where grown
  
• Not suited to tropical climates
  
• Not parasitic, climbing, or toxic to humans
  
• No wind or external animal dispersal
  
• Controlled by herbicides