The benefits of clearing invasive alien plants

Water shortages, loss of arable land, worsening veld fires, declining grazing quality, and lower cash crop yields all have one thing in common: invasive alien plants.

- David Gardner

There is hardly a farm in South Africa that has not been negatively affected in some way by these plants. Species such as slangbos (Seriphium plumosum L.), silver wattle (Acacia dealbata), and various species within the Eucalyptus and Lantana genera can cause significant problems for hardworking livestock and crop farmers, as well as game ranch owners.

At best infestations of invasive alien plants cause loss of agricultural potential, while bankruptcy, fines and farm repossessions are some of the worst outcomes. Although clearing these plants requires hard work and careful management, there are opportunities to recover at least some of the costs of clearing.

The impact of invasive plants

Invasive alien plants consume more than 6% of South Africa’s freshwater resources. They invade arable land at an alarming, ever-increasing rate. In many areas of the country they make commercial farming more difficult, or even impossible. In the northern bushveld areas of South Africa, encroached bush now covers a third of the entire landscape and grows at a rate of 0,6% of the total landmass per year.

In addition to posing a threat to commercial farming, invasive alien plants also increase the intensity of veld fires, such as the fires that occurred in Cape St Francis, Knysna and Cape Town within the past two years. Without urgent intervention, veld fires in certain parts of South Africa could reach the same intensity as the Australian veld fires that devasted large parts of the country late last year and earlier this year.