The city of Johannesburg in South Africa has over six million trees lining the streets and in the suburban gardens. It looks like a man-made forest from outer space. Just over a million trees are found in the parks and on the pavements, and the remainder are found in the suburban gardens.
The city was not always so green. When the Afrikaans settlers arrived on the Witwatersrand, there were very few trees as the highveld is a savannah or grassland system. However, the settlers soon planted acorn, oak and walnut trees among others.
During the gold rush of the 1800s mining companies started a nursery to test which trees were most appropriate for mine props. Blue gums were then planted in where there was plenty of water in the northern suburbs.
Other exotic trees, like oaks, planes and pepper trees were given to families for their gardens and to line the streets of the suburbs.
As the suburbs sprawled out, the streets were lined with trees that the colonials were familiar with such as oaks, planes and jacarandas.
The Melville Koppies Nature Reserve was made a reserve in 1959 and gives one an understanding of the indigenous look of the area.
The trees are far more important than being merely decorative. They have a genuine environmental purpose too. The trees control the greenhouse effect as the heat rises from the asphalt and the trees act as a natural coolant. Much of the carbon dioxide from cars exhaust fumes is absorbed by the trees and transformed into oxygen. The trees also reduce the noise levels of the city.
Trees are continually being planted, particularly in the suburbs with few trees and in the previously disadvantaged areas of Johannesburg. The Greening Soweto project, which started in 2006 by planting 6000 trees, is Johannesburg’s green revolution to maintain the city’s green suburbs. Its goal is to turn the extensive township into another urban forest by planting 200 000 trees. One of the problems of planting trees in Soweto is that the sewer systems are not deep enough and the pavements are too narrow to hold trees. The Johannesburg City Parks Department has given trees to residents to plant in their gardens in an attempt to grow more trees in the suburbs.
Johannesburg City Parks grows its own trees and supplies the surplus to the various communities for greening projects. The City Parks nursery grows around 100 000 seedlings each year to provide enough trees for the parks and pavements.