Family: Cupressaceae

Origin, Description & Uses
Shore juniper (Juniperus rigida var. conferta) is a low-growing, evergreen conifer native to the coastal sand dunes and rocky shorelines of Japan and Sakhalin Island (Russia). It forms a dense, spreading mat of soft, needle-like foliage that ranges from bright green to blue-green, reaching only about 12–18 inches tall but spreading up to 6–8 feet wide. This tough, salt-tolerant plant is prized in landscaping as a groundcover for erosion control on sandy slopes, rock gardens, and coastal areas. It also adds year-round texture and produces small, berry-like cones that attract birds.

Risks & Threats
In Hawaiʻi, shore juniper is currently considered Low Risk for becoming invasive. It does not appear to spread aggressively from cultivation, and there are no major reports of it naturalizing or outcompeting native vegetation in local ecosystems. However, as with any non-native plant, caution is advised: its dense growth could potentially displace low-lying native species if planted near sensitive habitats like dunes or coastal strands. For now, it is generally safe to use in managed landscapes.

High Risk Traits:

• Possible broad elevation range
  
• Naturalized in Alabama, Massachusetts, and SE Australia
  
• Other Juniperus species have become invasive
  
• May contain allelopathic chemicals
  
• Unpalatable to browsing and grazing animals
  
• High flammability could increase fire risk
  
• Tolerates many soil types
  
• Dense, mat-forming habit may exclude other vegetation
  
• Produces fleshy-fruits. May aid in seed dispersal by birds and other frugivorous animals
  
• Can reproduce vegetatively
  
• Reaches maturity in 2 years
  
• Tolerates glyphosate and may be resistant to certain other herbicides

Low Risk Traits:

• Grows in temperate climates. May only threaten higher elevation of tropical island ecosystems
  
• No reports of invasiveness or detrimental impacts
  
• Non-toxic
  
• Ornamental value
  
• Shade-intolerant
  
• Dioecious (and therefore self-incompatible)
  
• Seed production limited in introduced range
  
• Seeds require cold stratification
  
• Does not tolerate cutting or fires