Family: Piperaceae

Origin, Description & Uses
Piper nigrum is a tropical perennial vine native to Sri Lanka and southwestern India. It is widely cultivated around the world as the source of both black pepper and white pepper, two of the most commonly used spices in cooking. The plant produces long, climbing stems with heart-shaped glossy leaves and produces slender flower spikes that develop into small fruit clusters. It is typically grown on trellises or support trees in warm, humid, shaded conditions that resemble its native rainforest habitat.

Risks & Threats
Although Piper nigrum is not known to be naturalized in the Hawaiian Islands, it does possess traits that are cause for concern in tropical island environments. As a vigorous climbing vine, it can grow aggressively under suitable conditions and potentially smother or outcompete nearby vegetation if it escapes cultivation. While it is primarily managed as an agricultural crop, its reproductive capacity and growth form warrant caution. Ongoing evaluation is needed to determine whether it could negatively impact Hawaii, and care should be taken to ensure it remains contained and does not spread into natural areas.

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Grows well in tropical climates
  
• Naturalized outside native range
  
• Other Piper species have become invasive
  
• Shade-tolerant
  
• Tolerates many soil types
  
• Climbing habit
  
• Reproduces by seeds and vegetatively (rooting at nodes)
  
• Cultivated forms monoecious and self-compatible
  
• Reproductively mature within 3 years from vegetative propagation
  
• Seeds adapted for bird and animal dispersal
  
• Tolerates and resprouts from regular pruning

Low Risk Traits:

• Domesticated crop with long history of cultivation
  
• No reports of invasiveness or negative impacts in introduced range
  
• Unarmed (no spines, thorns, or burrs)
  
• Non-toxic
  
• Ornamental
  
• Recalcitrant seeds lose viability quickly (within one week)