Thrive removes invasive species

The Thrive team who cleared out invasive species are, front left to right Zikhona Mdalase, Given Ngdya, Welile Mgqalelo and Kingston Phiri and back from left Sylvester Omohan and Scott Louw.

The Thrive team, together with a team from Camps Bay, turned out in force on September 20 to help eradicate invasive plant species at East Fort near Chapman’s Peak.

The hack was organised by Klaus Minges, a keen invasive plant hacker who normally works alone to tackle a variety of invasive species.

The team worked on the gully up on East Fort to eradicate the stink bean (paraserianthes iophantha), which is among the species that came from Europe to South Africa many years ago.

The species tends to form very thick dense stands and because it is from other parts of the world, it does not have a competitor and tends to take over.

In the gully, where the invasive hack took place, tall stink bean trees formed a very thick forest, blocking the sunlight from the indigenous plants and preventing growth.

The challenge with stink bean, as with all other invasive species, is the fact that they consume large quantities of water and as South Africa and particularly the Western Cape, is a water scarce region, it is important that the species be eradicated.

These invasive species compete with our indigenous plants and take over their habitats. If they are left over extended periods of time they can change the soil composition drastically, resulting in indigenous vegetation being unable to re-establish itself.

They are a serious fire hazard because they contain oils. If a
fire starts where these invasive species are established, they burn very hot resulting in the fire spreading quickly.

The plant grows fairly shallow roots, enabling hackers to pull juvenile trees with little risk of breaking off the roots or of trees regrowing. However, an established tree needs to be cut very close to the ground if no herbicide is to be used. Trees cut at a higher level require the use of herbicide to prevent regrowth.

lZikhona Mdalase is a Thrive team supervisor.