Family: Lamiaceae

Origin, Description & Uses:
Teak (Tectona grandis) is a large, deciduous hardwood tree native to India and mainland Southeast Asia (Indo-China). Widely regarded as one of the world’s finest timber trees, it can grow over 100 feet (30 m) tall and develops a broad crown with large, rough leaves and clusters of small, fragrant white flowers. Its exceptionally durable, golden-brown wood is naturally resistant to decay, insects, and moisture, making it highly valued for shipbuilding, outdoor furniture, flooring, cabinetry, carving, and other high-quality construction uses. Teak is also planted as an ornamental shade tree and is cultivated extensively in plantations throughout the tropics.

Risks & Threats:
Teak is considered a low-risk species for the Hawaiian Islands. Although it has been widely planted in tropical regions around the world, it has not demonstrated the invasive characteristics associated with many high-risk tree species. Seedlings may occasionally establish near planted trees, but natural spread is generally limited and the species is not known to form dense, invasive populations that displace native vegetation. As with any non-native tree, responsible planting and monitoring are recommended, but teak is considered an appropriate choice where a durable timber or shade tree is desired.

High Risk Traits:

• Broad climate tolerance (0–48°C) and soil tolerance (if well-drained)
  
• Widely introduced outside native range across tropics
  
• Causes allergic contact dermatitis in humans
  
• Fire-tolerant; recovers via coppicing
  
• Valuable timber → intentionally dispersed by people

Low Risk Traits:

• Not naturalized, or weedy
  
• No spines, thorns, or burrs
  
• Not toxic to animals
  
• Shade-intolerant; requires full light
  
• No vegetative spread (no root suckers)
  
• Low fruit set (<1%); self-incompatible
  
• Seed production begins after 5 years
  
• No persistent seed bank (recalcitrant seeds)
  
• Susceptible to herbicides (e.g., 2,4-D)