Family: Orchidaceae

Origin, Description & Uses
Dendrobium mirbelianum, commonly known as dark-stemmed antler orchid or mangrove orchid, is native to northern Australia and parts of New Guinea. This striking tropical orchid is well known for its tall, upright, dark purple to nearly black cane-like stems and large, branching flower spikes. The showy blooms are typically fragrant and range in color from creamy yellow to greenish tones with darker markings. Adapted to warm, humid environments, it often grows in coastal forests and mangrove margins in its native range. Because of its bold structure and dramatic flower displays, it is cultivated as an ornamental plant in tropical gardens and by orchid enthusiasts.

Risks & Threats
In Hawaiʻi, dark-stemmed antler orchid is naturalized on Oʻahu but is currently considered low risk. While it can reproduce and persist outside cultivation, it has not shown aggressive invasive behavior or widespread ecological impacts. Like many orchids, it prefers specific growing conditions and does not typically form dense, smothering stands. However, as a naturalized species, it should still be monitored to ensure it does not expand into sensitive coastal or wetland habitats. Responsible cultivation and proper disposal of garden waste can help prevent unintended spread into natural areas.

High Risk Traits:

• Grows in tropical climates
  
• Naturalized on Oahu, Hawaiian Islands
  
• Other Dendrobium species may be weedy
  
• Reproduces by seeds
  
• Forms natural hybrids with other Dendrobium species
  
• Self-compatible
  
• Seeds dispersed by wind and intentionally by people
  
• As an orchid, presumably produces prolific numbers of seeds
  
• Limited, or missing biological and ecological information may limit accuracy or risk prediction

Low Risk Traits:

• No negative impacts documented to date
  
• Unarmed (no spines, thorns, or burrs)
  
• Non-toxic
  
• Epiphytic habit may limit dispersal vectors to wind or intentional planting