Invasive beetle threatens forest and fruit trees

Abstract

The polyphagous shot hole borer (PSHB) is an ambrosia beetle (Coleoptera: Curculeonidae: Scolytinae) native to Asia, together with its fungal symbiont Fusarium euwallaceae. PHSB attacks agricultural and forestry crops, street and garden trees, as well as several native tree species.

It has emerged as an important invasive pest killing avocado and other trees in Israel, California and the United States. The PSHB is one of three species in the Euwallacea fornicatus species complex, the taxonomy of which remains to be resolved.

The PSHB and its fungus were discovered in South Africa in 2017. The beetle has since then spread to a number of provinces in the country where it has infested and killed large numbers of trees. This small ambrosia beetle has an extraordinary wide host range. It has already been reported on many popular tree species grown in urban areas of South Africa, and is also a pest of pecan nut trees, avocado and other fruit trees. To help member countries address and manage the increased threats to forest health from invasive species such as PSHB, FAO facilitates the Forest Invasive Species Networks for Africa, Asia-Pacific, Europe and Central Asia and the Near East. These networks improves the exchange of information, knowledge and expertise on invasive species issues and enhance collaboration in the regions.