Family: Bataceae

Batis maritima (pickleweed, saltwort) is a salt-tolerant shrub native to the Americas that has become widely naturalized and invasive across all major Hawaiian Islands, including Niʻihau, Kauaʻi, Oʻahu, Molokaʻi, Lānaʻi, Kahoʻolawe, Maui, and Hawaiʻi Island. It is a strong colonizer of mudflats, fishponds, and other coastal wetlands influenced by tidal flooding. In these environments, it often forms dense, nearly monotypic stands, creating what is known as pickleweed marsh. These thick mats exclude most other plants and dramatically alter what should be species-rich native salt marsh communities.

Since its first record in Hawaiʻi in 1859, Batis maritima has spread widely and is known to displace native vegetation, including the culturally and ecologically important ʻākulikuli (Sesuvium portulacastrum) herbland. Its ability to invade soft, brackish coastal areas makes it a serious concern for wetland restoration and native wildlife habitat. Because it is a high-risk, invasive species, Batis maritima is not recommended for cultivation anywhere in Hawaiʻi, and coastal landowners are encouraged to protect and restore native salt marsh plants instead.

High Risk Traits:

• Environmental weed: smothers natives, invades ponds
  
• Smothering growth habit
  
• Spreads vegetatively via fragmentation
  
• Water-dispersed seeds and plant fragments
  
• Tolerates mutilation and disturbance
  
• Unintentionally dispersed by machinery/water
  
• Intentionally planted and sold
  
• Broad tropical/subtropical native range
  
• Already naturalized in Hawaii
  
• Tolerates wide soil range, including saline soils
  
• Unpalatable to grazing animals

Low Risk Traits:

• No spines, thorns, or burrs
  
• Not toxic to animals or humans
  
• Not a significant pest or pathogen host
  
• Does not create fire hazards
  
• Susceptible to herbicide control