Long-thorn kiawe (Prosopis juliflora)
Considered very invasive and is on the Noxious Weed List.
- Different from common kiawe (Prosopis pallida), long thorn kiawe can grow as a rambling shrub or tree, and has 6 cm (2.5 in) long thorns (common kiawe grows into a tree and has thorns that are either absent or less than 3 cm (1 in) long.
- Native to Africa, introduction history is unknown, but first noted invading in 1978. Possibly introduced for agriculture or accidentally introduced.
- Grows in dense thickets and crowds out native coastal plants, prevents beach access
- Long, sturdy thorns able to pierce slippers, shoes and even truck tires.
- Produces thousands of seeds per year, which are carried by water and animals
- Despite its relative value as cattle fodder, it encroaches on pastureland where introduced (e.g. South America, Asia and Australia) and is considered a noxious weed.
- Kauai: Populations on the beaches of Mahaulepu, Barking Sands, and the area between Waimea Bridge and Kekaha. Populations also exist on Niihau. KISC is working with partners to control populations, although a large population on military property at the Pacific Missile Range Facility at Barking Sands remains inaccessible at this time.
- Oahu: Populations along the leeward coast and along canals from Kapalama to Waianae. Not considered eradicable by OISC, landowners are asked to control this pest wherever possible.
- Maui: None known.
- Molokai: One recent planting of a couple dozen plants found along property line at beach access to Papohaku Beach. Not currently a control target for MoMISC.
- Lanai: Presence/absence unknown.
- Kahoolawe: None known.
- Big Island: Presence/absence unknown.