Pest of the Month – Koa Rust (Atelocauda digital) Hosts: Infects a wide range of Acacia species, including A. koa, mangium, auriculiformis, aulococarpa, crasicarpa, leptocarpa, mearnsii, and polystacha. Distribution: Occurs on all major Hawaiian islands except Lāna‘i. Damage: This rust disease is not fatal to koa trees. Severe symptoms (witches’ brooms) are mainly confined to several or …