If you spot invasive species in any of our parks and reserves, please take a photo and notify those in charge of conservation of the area.

The most common alien species are:

• Acacia mearnsii (Black Wattle)
• Saligna (Port Jackson Willow)
• Cyclops (Rooikrantz)
• Melanoxylon (Blackwood)
• Lantana camara (Lantana)
• Chromolaena odorata (Triffid weed)
• Solanum mauritianum (Bugweed)
• Hakea sericea (Silky hakea)
• Pinus pinaster (Cluster pine)
• Melia azedarach (Syringa or Persian lilac)

When you buy firewood opt for the exotic type (don't buy indigenous).

People move around the world all the time, often taking flowers and plants with them. Please don’t do that! If these alien species find ideal conditions in their new home, they often overwhelm indigenous plants because their natural enemies didn't travel with them.

During the 19th century, several species of Australian acacias were introduced to South Africa. In their native habitat the millions of seeds produced would be eaten by insects, but our own 6-legged critters don't care for it as much.  The result is that the Australian acacias take over local plants, particularly the fynbos in the South-Western Cape. Fires are essential for the long-term survival of fynbos, but the acacias recover far more rapidly. Large areas of natural fynbos have been taken over as a result.

The fynbos face a second problem, also due to an alien species.  Approximately 20% of the fynbos plant species rely on indigenous ants to protect their seeds by taking them underground. Argentine ants drive these local ants away in the South-Western Cape, and also don't bother with the fynbos seeds. 

This is just one indigenous plant species that is suffering from the threat of alien invasion. What more can we do to help?

• Choose indigenous plants for your garden. They will grow better, attract the local wildlife and use less water than exotic species.
• Support projects that remove alien species and plant indigenous species across large areas.

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