Family: Fabaceae

Origin, Description & Uses
Pueraria montana var. thomsonii (kudzu vine) is native to tropical and subtropical regions of Asia. It is a fast-growing, perennial vine in the legume family known for its vigorous climbing habit and ability to spread rapidly over vegetation, fences, and structures. The plant produces large, lobed leaves, purple flowers, and thick, starchy roots. In its native range and elsewhere, kudzu has been used for erosion control, forage, ornamental cover, and in traditional medicine and food applications, particularly for its edible roots and starch.

Risks & Threats
Kudzu vine is naturalized on Kauaʻi, Oʻahu, and Maui, and is potentially naturalizing on Hawaiʻi Island. It is widely recognized as an aggressive invader due to its extremely rapid growth and ability to smother and outcompete native vegetation, forming dense blankets over forests, shrublands, and disturbed areas. Once established, it is very difficult to control and can significantly alter ecosystems by blocking sunlight and suppressing native plant regeneration. Because it is naturalized and possesses traits that are cause for concern, this species could detrimentally impact tropical island ecosystems. Choosing low-risk or native alternatives is strongly recommended whenever suitable options are available.

High Risk Traits:

• Naturalized beyond native range
  
• Agricultural, forestry, and environmental weed (causes tree mortality, excludes native species)
  
• Congeneric weedy species exist
  
• Host for recognized pests/pathogens (e.g., soybean rust reservoir)
  
• Climbs and smothers other vegetation
  
• Forms dense monocultures
  
• Geophyte (massive taproots, resprouts vigorously)
  
• Reproduces vegetatively by runners and rhizomes
  
• Tolerant of shade, wide soil conditions, and mutilation/fire
  
• Propagules dispersed intentionally by people, by birds/mammals (ingestion), and unintentionally via machinery
  
• Persistent seed bank (>1 year)
  
• Difficult to control (requires repeated herbicide treatments over many years)

Low Risk Traits:

• No spines, thorns, or burrs
  
• Not toxic to animals or humans (palatable as livestock forage)
  
• Low viable seed production (not a prolific seed producer)
  
• No wind dispersal adaptation
  
• No external animal attachment mechanism