Koa wilt it starts to produce microconidia, eventually clogging the xylem. Once the Koa tree dies, the fungus invades all tissues and, upon reaching the dead plant surface, sporulates profusely producing macroconidia and chlamydospores. The fungus can survive saprophytically in the soil, as either mycelium or as any of its three spore types mentioned. The chlamydospores, as the resting spores, survive the longest in the soils, usually under cold conditions. Koa trees occupy dry to mesic areas on the islands of Kauaʻi, Oʻahu, Molokaʻi, Lānaʻi, Maui, and Hawaiʻi in elevations of 80 to 8,000 feet with 0 to 100 inches of rain.
Koa people as the centre, they extended north as far as Kynuna. Their western boundary lay around Middleton Creek, wshile to the east, their frontier was at Winton and Sesbania. Their southern limits were around Cork. Neither circumcision nor subincision played any part in the Koa's initiatory rites into manhood. At least one Koa Bora ground, a gibber clearing threaded with portoluca, used to exist close to the homestead on Carisbrooke Station, southwest of Winton. Comparatively little is known of the Koa, and, in one modern tradition of whites in the area, they just 'melted away' when Europeans began to settle in