South Africa uses insect army to tackle invasive plant species | Global Ideas | DW | 11.05.2022

Visit the new DW website

Take a look at the beta version of We're not done yet! Your opinion can help us make it better.

  1. Inhalt
  2. Navigation
  3. Weitere Inhalte
  4. Metanavigation
  5. Suche
  6. Choose from 30 Languages

Global Ideas

South Africa uses insect army to tackle invasive plant species

Can planthoppers help fight the spread of water hyacinth in South African waterways?

Watch video 05:49

Grasshoppers versus water hyacinths in South Africa

Water hyacinth, an aquatic weed from South America, is widely regarded as one of the world's most problematic plants. 

It has spread across the globe and invaded local waterways, making them difficult to access. It also presents an environmental challenge by outcompeting native species and creating a dense mat of leaves across the water's surface that prevents sunlight from reaching plants and animals below.

Since arriving in the early 1900s in South Africa, water hyacinth has spread throughout the country. Attempts to control its growth using chemical herbicides or removing it by hand or machinery have had little impact. 

A water hyacinth planthopper, Megamelus scutellaris, sits on a hyacinth leaf showing the damage inflicted on the invasive plant by the insect

The planthopper has proven to be an effective biological control agent against the invasive plant in South Africa

In 2019, the Center for Biological Control(CBC), part of Rhodes University in the country's Eastern Cape Province, introduced a new tool in the fight to control the invasive species: a native insect called the planthopper. 

Since 2019, the CBC has bred over 1 million planthoppers at a special facility and put the insect army into action on the Hartbeespoort Dam, where hyacinth covers more than 40% of the surface area of the water. 

A film by Jason Boswell

An aerial viewing showing the vast mats created by the free-floating weed

The plant accumulates in certain sections of the dam effectively blocking out sunlight and clogging the waterway for boat traffic

DW recommends

Audios and videos on the topic