Koa wilt They are a dominant forest species. Koa wilt has been found on the islands of Kauaʻi, Oʻahu, Maui, and Hawaiʻi. Most diseased trees are found at elevations below 3,000 feet. However, it has also been observed at elevations as high as 7,000 feet. Fusarium, the primary cause of Koa wilt, May be found in a variety of environments but thrives with the high temperatures and moist soils of Hawaii. It survives in the soil. "F. oxysporum" is a soil-borne pathogen, and currently sanitation, controlling the initial inoculum, is the best means to control it. One should avoid bringing infected soil
Koa wilt species of koa-finches, "Rhodacanthis palmeri" and "R. flaviceps", which fed on green koa seed pods. These species are now extinct due to habitat loss and avian malaria. It is important to preserve the remaining koa populations to helpt to avoid further native bird extinctions. Koa also has great cultural importance for native Hawaiians. The name “koa” means "brave, bold, fearless" or "warrior" in Hawaiian. Koa wood was used extensively in ancient Hawaiian society for constructing houses, spears, tools, canoe paddles, kahili (feathered standards of royalty), calabashes, ceremonies, and surfboards. Canoes were, and still are, carved from the trunks of koa