City inspectors on the lookout for shot hole borer beetle

The shot hole borer beetle.

The City of Cape Town has appointed teams to inspect trees in the Somerset West area for possible infestations of the polyphagous shot hole borer (PSHB) beetle.

The City has removed and incinerated 156 trees infested by the PSHB since April 2019, when the pest was detected on trees in the northern parts of Somerset West.

Sightings of the PSHB were first reported to the City’s invasive species unit (ISU) in April 2019.

Since then, an experienced invasive species removal team from the City has visited 361 sites across Cape Town to inspect trees that were suspected of being infested by the PSHB. They found that 160 trees in Somerset West have been infested, of which 156 were chipped on site, carefully removed under cover of heavy duty plastic, and incinerated at appropriate sites. The City is busy removing the remaining four infested trees. 

“About 130 of the infested trees were removed from privately owned residential properties in the northern parts of Somerset West, and the rest from City-owned land – mainly road reserves and parks. At this stage, it seems that the pest is confined to this area only,” said the City’s mayoral committee member for spatial planning and environment, Marian Nieuwoudt. 

The ISU has recently appointed a team of temporary workers through the Expanded Public Works Programme (EPWP) to assist with inspecting trees in and around the Somerset West area to record the extent and spread of the pest.

“I’m asking residents to please allow these workers access to their properties so that they can inspect the trees for any possible infestation. The workers will be wearing dark green shirts, and must have an identification card with their name, photo, staff number, and City logo in their possession. We also encourage members of the public to be on the lookout for possible infestations on their properties. This beetle is extremely harmful and devastating,” said Ms Nieuwoudt. 

There were reports about alleged infestations from other parts in Cape Town. “However, when we went out to inspect these trees, we found that it was a false alarm. I want to thank our residents for their vigilance in reporting possible sightings to the City, and I also want to commend the Invasive Species Unit for the swift response which I’m sure has assisted us thus far in preventing the pest from spreading,” said Ms Nieuwoudt. 

What to look for:

Indications that the tree may be infested include tiny (not more than 2mm) holes directly into the tree (not under the bark); oozing of sap or resin, frass (millings), and later partial or full dieback of the tree. The insect is black, about 2mm in size, and is sometimes seen flying.

More information on identification and a list of known host tree species is available on the ISU’s website at 

The spread of the PSHB pest is also buoyed by transporting infested material and infested firewood. Residents are advised not to cut down or transport possibly infested trees and firewood, but rather to report the infestation to the ISU. 

“Residents should also be on the lookout for dishonest or uninformed contractors who offer to treat, cut and transport infested material. The City is currently assisting residents with removal of infested material at no cost. In fact, the ISU has spent nearly R1.3 million over the past 10 months to remove infested trees,” said Ms Nieuwoudt. 

Call all 0860 103 089 for more information.