Invasive alien plants

Invasive alien plants can outcompete native flora, modifying the natural environment and threatening the survival of indigenous biodiversity.

Lantana is the most problematic alien plant species here at Malilangwe. During the rainy season, its seeds are transported down the Chiredzi River from the communal lands of Zaka District, where it is particularly prevalent.

A study conducted by Allan Tarugara showed that cover of lantana in Zaka District ranges from 12 – 21.5%, depending on vegetation type. With this level of invasion upstream, our management team has resigned itself to a never-ending battle.

Every year, at the beginning of the dry season, we deploy a lantana control team to the riverine vegetation flanking the Chiredzi River. Lantana shrubs are cut and treated with herbicide, and seedlings are pulled by hand. Lantana will probably never be eliminated from Malilangwe, but this strategy has kept its invasion under control.

Other problematic alien plants include Albizia lebbeck, Calotropis procera, Solanum seaforthianum, Catharanthus rosea, Psidium guajava, Opuntia ficus-indica, and Dolichandra unguis-cati.

The gardens of the original homesteads and safari camps have been the primary source of alien plants, and we’ve employed a systematic programme of eradication and follow-up in these areas over the past 30 years. To prevent unwanted introductions, planting of certain species is prohibited, and foraging for captive animals has been purposefully purchased from areas with low levels of problematic species.