Family: Poaceae

Origin, Description & Uses
Cenchrus clandestinus (kikuyu grass) is a fast-growing perennial grass native to Eritrea and other parts of southern tropical Africa. It forms dense mats of bright green grass with creeping stolons and rhizomes that allow it to spread aggressively across the landscape. Kikuyu grass has been widely planted in tropical and subtropical regions as a pasture grass, lawn grass, and for erosion control because it tolerates grazing, drought, and repeated mowing. In Hawai‘i, it has become naturalized on Kaua‘i, O‘ahu, Moloka‘i, Lāna‘i, Maui, and Hawai‘i Island. It occurs in dry to mesic exposed habitats, agricultural lands, disturbed forests, and alien-dominated plant communities from low elevations up to over 2,000 meters. It was first collected on Lāna‘i in 1923.

Risks & Threats
Kikuyu grass is naturalized in Hawai‘i and possesses traits that are cause for concern in tropical island ecosystems. Its rapid growth and dense spreading habit allow it to outcompete native vegetation, smother seedlings, and dominate disturbed habitats and open forest areas. The species can alter natural plant communities, increase management costs in conservation areas, and hinder native forest regeneration. Because it spreads both vegetatively and by seed, kikuyu grass can be difficult to control once established. Its ability to thrive across a wide elevational range and in many habitat types increases its invasive potential throughout the islands. Due to these risks, this species could detrimentally impact Hawai‘i’s ecosystems, and planting low risk or native alternatives is recommended whenever suitable alternatives are available.

High Risk Traits:

• Widely naturalized beyond native range
  
• Naturalized on all main Hawaiian Islands (Kaua‘i, O‘ahu, Moloka‘i, Lana‘i, Maui, and Hawai‘i)
  
• Noxious weed in the U.S. (federal & California)
  
• Agricultural weed in many countries (orchards, vineyards, pastures, potatoes)
  
• Congeneric weeds exist (federal noxious list)
  
• Allelopathic (kills other plants)
  
• Apomictic (asexual seed reproduction)
  
• Reproduces vegetatively (rhizome fragments)
  
• Fast-growing (short generation time)
  
• Propagules spread unintentionally (plant fragments)
  
• Propagules spread intentionally (pasture/lawn grass)
  
• Seeds survive gut passage (spread by grazing animals)
  
• Tolerates mutilation, cultivation, fire
  
• Broad climate tolerance (0–3,500 m elevation)
  
• Wide soil tolerance

Low Risk Traits:

• No spines, thorns, or burrs
  
• Highly palatable (not unpalatable)
  
• Not shade-tolerant (requires high light)
  
• Not a prolific seed producer
  
• Well controlled by herbicides