The pavement trees of Kensington form part of a huge man-made forest. They perform a vital function in the micro-ecosystem. This man-made forest is almost 118 years old and home to many birds. Our urban forest contributes to healthy air and lower temperatures in summer.
Some history behind our trees
Kensington is about 115 years-old and was founded by Max Langerman who lived in the suburb on the road that was named after him, Langerman Drive. The suburb was proclaimed in 1902 from a portion of the farm Doornfontein. In 1902 the streets of Kensington were laid out and were heavily planted with trees by William and Stanley Nelson of Nelsonis Nurseries. They planted Oaks, Pin Oaks, London Planes & Jacaranda trees along the pavements. They covered a distance of 106 kilometers. It is said the project took 9 months to complete. In their natural habitat, these trees have been known to live for centuries, but here in Johannesburg, they are not necessarily well-adapted to the climate and so their life span seems to be more limited.
Driving along certain roads of Kensington it was noticeable that pavement trees were dead, dying or appeared sick. At first it was thought that the PSHB Beetle was infesting the pavement trees of Kensington. In order to assess the general health of pavement trees and garner an objective view of the overall status of public trees in our suburb, an audit was undertaken.
Auditing the Kensington Pavement Trees
The tree audit covered about 60% of Kensington streets. With a group of 4 Jeppe Girls we traversed as many streets as possible and counted each gap, stump and tree on the pavements. Trees were observed as either dead, dying, sick or in health. The aim was to quantify how many trees will need to be removed and replaced. We knew that once we had the numbers, we would be able to raise funds and implement a project to address the challenge.
Many of the trees are older than the houses, with the average house being over 60 years old. The most common trees are the Oak Tree and the Jacaranda Tree. There are London Plane trees along a few of the streets such as Protea and New York. There are also many Pin Oak trees that have attained giant size. At least 80% of the pavement trees are not indigenous, they are not water wise and have invasive root systems. Because the trees are exotic and not ideally adapted to the Johannesburg climate, the urban forest is aging and reaching the end of the life cycle.
Interestingly, the audit team did not observe any major PSHB beetle infestation of the pavement trees, although private trees in Kensington gardens are infested, especially exotics, the public trees appear to be free of the PSHB beetle
Some audit stats:
· About 60% of Kensington was covered.
· We counted a total of 2 542 trees, stumps & gaps on the pavements of 24 streets.
· 2 196 trees were counted & observed.
· As of November 2019, 346 replacement trees required.
It was observed that the Oak trees are generally unhealthy. Many Oaks are dead, dying or sick (maybe Oak fever). All the Oak trees will need to be replaced over a 5-year period. It was observed that the Pin Oak trees are generally healthy and will only need to be replaced in another 10 years. The London Plane Trees are about 50% healthy and 50% sick and will need to be replaced over a 10-year period
Then there are the iconic Jacarandas to consider:
Jacarandas are sub-tropical trees native to south-central South America. They are invasive trees and there are laws against planting them. They were first introduced to South Africa in the late 19th Century. Johannesburg’s first Jacaranda tree was planted in Doornfontein and Kensington’s trees were planted in 1902. The trees are badly pruned, suffering from wood termite, some roots are waterlogged, have bark disease, and many trees are slowly fading away.
We need to replace the Jacaranda trees over the next 10 years. Because of their prohibited status, we approached the Head of Biosecurity at the Department of Environment, Forestry and Fisheries about the challenge: the current Jacaranda Avenues are so Iconic to Kensington, it would feel like a sad destruction of our heritage to replace them with something else. He said that we should approach his department when we are ready with our replacement plan – he thinks that they would be able to give us a special dispensation to replace only the street Jacarandas to preserve that legacy. Should we replant Jacarandas in all streets where they currently grow? Or limit them to just a few streets and replace the others with indigenous trees? Please give your thoughts in the comments section below.
The urban forest of Kensington, Malvern and Bez Valley is aging and needs replacement over the next 10 years. Research has proven that the pavement trees improve the quality of air, capture carbon and keep the suburbs cool in summer. Indigenous trees also attract natural biodiversity in the form of pollinators and birdlife, which adds to the natural quality of our leafy suburb. They are a key contributor to people’s sense of wellbeing and therefore the role of the trees is tangible and vital.
City Parks is responsible for pavement trees. But they don’t have sufficient budget to remove & replace the pavement trees. And yet new trees must be purchased & maintained very soon. We need to do something NOW to replace the trees in Kensington, Malvern & Bez Valley over the next 10 years.
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