What is the Polyphagous Shot Hole Borer (PSHB) beetle and why is it a problem in Johannesburg?

The Polyphagous Shot Hole Borer (PSHB) beetle, scientifically known as Euwallacea sp., is an invasive pest that poses a significant threat to various tree species in different parts of the world. The beetle is native to Southeast Asia and has spread to other regions, including North America, South America, and Africa.

The PSHB beetle is relatively small, measuring about 2-3 millimeters in length. It has a dark brown or black body and is often difficult to spot due to its small size. The beetle gets its name from the shot hole-like entry and exit marks it leaves on infested trees.

The primary concern with the PSHB beetle is its symbiotic relationship with a fungus called Fusarium euwallaceae. The beetle carries the fungus within its body and introduces it into tree hosts during its burrowing activity. The fungus then colonizes the tree, causing a disease known as Fusarium Dieback.

The burrowing activity of the PSHB beetle and the spread of the fungus can lead to serious damage and mortality of affected trees. The beetle primarily attacks various tree species, including avocado, sycamore, oak, willow, and many others. Infested trees exhibit symptoms such as branch dieback, stem discoloration, gumming, and small exit holes.

Controlling the spread of the PSHB beetle and the associated Fusarium fungus is challenging. Measures include early detection, monitoring, quarantines, removal and destruction of infested trees, and the use of integrated pest management strategies.

Efforts are underway in different regions to study and manage the PSHB beetle and its impact on trees. It is important to report any suspected infestations to local agricultural or environmental authorities to help prevent the spread of this destructive pest.

What can you do about the Shot Hole Borer (PSHB) beetle?

In Johannesburg there are a number of people that have been trying to prevent the Shot Hole Borer Beetle from spreading. Notably Councillor Trulluck in Parkhurst / Parkview / Parktown has made serious efforts since at least 2019. Councillor Trulluck can be contacted on:

ttruluck@gmail.com

You can get more information on this site:

https://www.fabinet.up.ac.za/pshb