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
Primitive koa finch Primitive koa finch fossils have been found on Maui and Oahu. It is believed that it inhabited lowland dry forests and savannas, where dominant plant species included "ka palupalu o kanaloa" ("Kanaloa kahoolawensis"), "aalii" ("Dodonaea viscosa"), "loulu" ("Pritchardia" spp.), and "koaia" ("Acacia koaia"). Unlike other species of "Rhodacanthis", "koa" ("Acacia koa") was not present in significant numbers in its habitat. The primitive koa finch was a granivore, with a bill adapted to eat the hard seeds and pods of legumes, especially "ka palupalu o kanaloa" ("Kanaloa kahoolawensis") and "koaia" ("Acacia koaia"). It may have also taken caterpillars and "aalii" ("Dodonaea