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This little beetle eats its way through tree-lined cities in South Africa – and will cost the economy R275 billion

The potential economic consequences of the polyphagous shot hole drill in South Africa amount to a major one R275 billion over the next ten yearsand municipalities will have to bear the cost of these costs if nothing is done to turn the tide, say researchers from Stellenbosch University (SU).

The shot-hole drill was first discovered in South Africa in 2012 and has since spread to eight of South Africa’s nine provinces, making it the largest current outbreak of this invasive plague worldwide. While most of South Africa’s most notorious invasive species are problematic in rural areas, this aggressive invader will have the greatest impact on trees in urban areas.

This estimate is the result of a collaboration between economists, ecologists and other scientists at Stellenbosch University and the University of Pretoria.

Instead of basing its findings on existing data, the team used a modeling approach based on projected consequences – thus seeking to simulate possible future effects of this invader if nothing is done to prevent it from spreading further.

Prof Francois Roets, an ecologist in the SU Conservation Ecology and Entomology department and one of the co-authors, is helping a tree-lined city like Stellenbosch to lose 20,000 of the great old oaks and plane trees that line its streets are. In Somerset West, where the bullet hole was first discovered four years ago, more than 10,000 trees have been infected and some of the oak trees are now dying.

The data show that if nothing is done to stop the spread from 2020 to 2030, 65 million city trees will have to be removed and safely removed. The potential economic impact of business as usual over that period will be R275 billion, the researchers said.

“We need a national policy and coordinated strategy for municipalities to stop this beetle in its tracks,” he warns. To date, the polyphage hole drill is not yet under the Alien and Invasive Species Regulation, which makes it difficult for municipalities to respond effectively, ”says Prof Martin de Wit, an economist at the SU School for Public Leadership.

To date, no thoroughly tested and approved insecticide or fungicide has been registered in South Africa to effectively treat gunpowder borer infections, at least not for city trees. “Anyone who tells you that they will save your tree with chemicals and fungicides is probably lying and will break the law,” said Prof Roets.

“A coordinated strategy to deal with the invasion of South Africa will require a revision of legislation and the creation of policies regarding biological invasions. At present, there is no coordinated management of invasive species in urban ecosystems, a critical oversight.


To read: South Africa plans a massive green ‘gold rush’

This little beetle eats its way through tree-lined cities in South Africa – and will cost the economy R275 billion

Source link This little beetle eats its way through tree-lined cities in South Africa – and will cost the economy R275 billion

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