- An invasive beetle known as the polyphagous shot hole borer (PSHB) has infested over 5,000 trees across Cape Town, threatening the city’s urban forest.
- The City of Cape Town is removing infected trees and holding training sessions to educate residents on preventing further spread.
- The public is urged to follow safety measures and report infestations to help protect Cape Town’s remaining trees.
The city is facing a significant threat to its urban forest due to an alarming infestation of the polyphagous shot hole borer (PSHB) beetle.
Over 5 000 trees have been affected citywide, with 348 infested trees recorded in the southern suburbs as of Friday 25 October this year.
Areas affected include Alphen in Constantia, Newlands, Wynberg, Rondebosch, Mowbray, Claremont, Kenilworth and Observatory along the Liesbeek River.
Highly susceptible species like the Boxelder, Weeping Willow and English Oak are among those impacted.
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To date, 172 trees have been removed, and 21 tree species in the southern suburbs are affected.
The City of Cape Town is employing pruning, tree removals and the use of chipping and solarisation to manage the pest.
Ineffective methods
Chemical methods such as pesticides and fungicides have proven ineffective, noted Eddie Andrews, Deputy Mayor and Mayco member for spatial planning and environment.
“The PSHB poses a serious threat to Cape Town’s urban forest,” Andrews warned, urging collaboration among residents and businesses handling plant material. “We need the public to realise the seriousness of the situation and the huge threat PSHB poses to our trees in Cape Town.”
To assist the public, a free training session was held on 11 November at Alphen Hall, Constantia Main Road in Constantia.
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City officials covered essential information, including how the beetle spreads, the threat it poses and infestation details across Cape Town.
Andrews highlighted the role that businesses and residents must play, particularly those involved in gardening, landscaping and tree management. The training addressed protocols for managing infested biomass, such as identifying infested trees, safe disposal methods and precautions when handling equipment to prevent spreading the pest.
Signs of infestation include branch dieback, gumming, entry and exit holes, and staining on the bark.
Andrews emphasised that “infested trees must be chipped on-site” as moving the material can lead to further spread. The public is advised against buying and moving firewood from infested areas.
The City aims to verify reports within 10 working days, although this timeframe may vary based on reported sighting volumes.
As Andrews stated: “We need the support and collaboration of residents and businesses working with plant material to prevent the spread of the pest”.
- To report PSHB sightings, email invasive.species@capetown.gov.za or call 021 444 2357.
