Queen of the Night, a major invasive species, originates from Brazil, and has spread widely in South Africa forming dense stands, reaching heights of up to 6 m. Birds largely spread the seed. A solution is now at hand.
The Queen of the Night Cereus jamacaru BioControl Project is a pioneering effort that addresses the ecological challenge posed by a succulent Alien Invasive Plant (AIP). Its vigorous spread, fuelled by it being planted in gardens abutting natural areas and spread by birds eating its fruit caught the attention of conservationist John Wesson in 2007.
The most effective long-term solution is biological control. Gauteng Nature Conservation was approached to obtain the first batch of mealybug-type aphids called Hypogeococcus pungens. These were then attached to large stands of Queen of the Night plants in one valley in the De Wildt area. The plan was to create a ‘nursery’ for the bugs, and a ready source, in time, to start the treatment of plants on a wider scale. After around five years the project could start in earnest. Plant stems were cut around 400m in length, with the bugs on them, and ready to be attached to host Queen of the Night plants. Each excursion sees about fifty stems with around 150 colonies being placed at a time.
In general, it takes from two to five years for the bugs to take hold, depending on the climatic conditions, but they rapidly attack the growth points and flowers, stopping seed production. Large plants can take up to ten years to die off completely but as indicated from an early stage they cannot reproduce or spread anymore.
This project showcases the power of volunteers embracing ecological solutions that work in harmony with nature, to restore balance in ecosystems. This initiative not only mitigates the spread of an AIP but also paves the way for raising awareness amongst people on South Africa’s biodiversity. Through research, strategic partnerships, and a commitment to preserving South Africa’s natural heritage, the Queen of the Night Bio-Remediation Project sets a remarkable precedent in the realm of environmental stewardship.
These bugs will be available in the Waterberg shortly. If you are interested contact ken@waterbergdevelopment.co.za