The biological control process and describe the next steps in our international collaboration with researchers in Indonesia to find appropriate natural enemies of albizia

Abstract

Classical biological control refers to the intentional introduction of a natural enemy from the native range of an invasive species into the presumably enemy-free space of the invaded range. The objective of biocontrol is for introduced agents to establish permanently and provide long-term suppression of an invasive species, as well as the restoration of ecological balance. The island of Hawaii is negatively impacted by an invasive tree native to Indonesia, albizia (Falcataria moluccana, known locally in Indonesia as sengon or salawaku), which destroys native landscapes and threatens Hawaii businesses and homes with many millions of dollars in damage. We have completed exploratory surveys in Indonesia searching for specialist natural enemies of this invasive tree that will eventually undergo extensive host specificity and impact testing prior to release in Hawaii. Two high priority candidates for further study include gall forming eriophyid mites and a stem boring weevil. Also among early prospects is a rust fungus (Uromycladium falcatarium) that galls new growth and is a major problem for albizia plantations in the Philippines and Indonesia. Here we discuss the biological control process and describe the next steps in our international collaboration with researchers in Indonesia to find appropriate natural enemies of albizia.