Koa wilt Koa wilt Koa wilt is a relatively new disease to Hawaii, discovered in 1980. Koa wilt is caused by a forma specialis of the fungus "Fusarium oxysporum", which is now abundant in Hawaiian soils and infects the native Acacia koa tree, a once-dominant species in the canopy of Hawaiian forests. Fusarium oxysporum f.sp. koae is believed to have been brought into Hawaii on an ornamental acacia plant. Fusarium fungi clog the tree xylem, causing significant wilt and mortality among these beautiful and iconic Hawaiian trees. The host for Koa wilt is Acacia koa, a tree that is native and endemic
Wahiawa Botanical Garden The property was transferred to Honolulu in 1950, and opened as a botanical garden in 1957. It is open seven days a week, from 9am to 4 pm. The Garden's collections include: Blue Ginger ("Dichorisandra thyrsiflora"), Hāpuu ii ("Cibotium chamissoi"), Koa ("Acacia koa"), Blue Jacaranda ("Jacaranda mimosifolia"), "Nageia nagi", "Angiopteris evecta", Shaving Brush Tree ("Pseudobombax ellipticum"), Autograph Tree ("Clusia rosea"), Nutmeg ("Myristica fragrans"), Allspice ("Pimenta dioica"), Travellers' Palm ("Ravenala madagascariensis"), "Chrysophyllum oliviforme", Common Screwpine ("Pandanus utilis"), "Parkia javanica", Guanacaste ("Enterolobium cyclocarpum"), Candle Tree ("Parmentiera cereifera"), Elephant Apple ("Dillenia indica"), Moreton Bay Fig ("Ficus macrophylla"), Queensland Kauri ("Agathis robusta"), "Brownea macrophylla",