Family: Elaeagnaceae

Origin, Description & Uses
Elaeagnus angustifolia, commonly known as oleaster or Russian olive, is a deciduous tree native to western and central Asia, including regions of Russia, Iran, and Kazakhstan. It typically grows 20–30 feet tall with a rounded crown and silvery-green, narrow leaves. In spring, it produces small, fragrant yellow flowers, followed by small, olive-like fruits that are edible and sometimes used in jams or traditional medicine. This species is often planted for ornamental purposes, windbreaks, and erosion control due to its hardy nature and ability to tolerate poor soils and drought conditions.

Risks & Threats
Although Elaeagnus angustifolia is not currently known to be naturalized in the Hawaiian Islands, it exhibits characteristics that raise ecological concern. It is highly adaptable, produces abundant seeds that can spread quickly, and can outcompete native vegetation, potentially altering habitats and reducing biodiversity. Its ability to fix nitrogen may also disrupt nutrient cycles in fragile tropical soils. Because of these traits, introducing this species could negatively impact Hawaii’s unique island ecosystems. It is recommended to choose low-risk or native alternatives for landscaping or erosion control to protect local biodiversity and maintain ecological balance.

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Thrives in temperate climates (may only pose a threat to higher elevations in tropical island ecosystems)
  
• Widely naturalized in North America
  
• An agricultural and environmental weed
  
• Other Elaeagnus species have become invasive
  
• Often armed with coarse thorns
  
• Becomes less palatable with increasing age
  
• Pollen may be allergenic to susceptible individuals
  
• Shade-tolerant
  
• Tolerates many soil types
  
• Forms dense thickets
  
• N-fixing (may alter soil chemistry)
  
• Produces viable seeds
  
• Seeds dispersed by birds, mammals and water
  
• Seeds may remain viable in the soil for 3 years
  
• Able to coppice and resprout after cutting or damage

Low Risk Traits:

• Palatable foliage when young
  
• Ornamental and medicinal purposes
  
• Self-incompatible
  
• Not reported to spread vegetatively (although able to sucker if damaged)
  
• Herbicides may provide effective control