During National Water week on the 18 - 24 March, the Impi's and Lead Instructor Pieter Pretorius started the Water hyacinth project on one of the dams on the Bhejane property.
Water hyacinth (Eichhornia crassipes) is a perennial, aquatic plant, native to the Amazon Basin of
Through some research Pieter found a possible solution for the control of these weeds; The Water hyacinth Mite and Mirid. These insects are the natural enemies of these plants and we managed toobtain a few thousand of these insects and released them onto the weeds. These Mites (Orthogalumna terebrantis) and Mirid's (Eccritotarsus catarinensis) feed and lay their eggs in these Water hyacinth weeds. Mites will feed on the older weeds, and clear feeding tunnels can be seen on the leaves when held up to the light. They will lay their eggs in the younger plants. These larval and nymphal tunnels affect up to 90% of the surface area of the leaves and reduce the photosynthetic capability of the leaves and reduce the vigour of the plant.
The Mirid's feed on the leaves, causing yellowing/ browning of the leaves due to the extraction of chlorophyll. Mirid's however prefer only the mature stands of water hyacinth, where the leaves protect them from excessive cold and heat.
Thank you to Instructor Pieter and the Impi's for their hard work and we look forward to seeing the results in the near future! Keep following our Facebook page and blog for updates on the progress
For additional information on the Water hyacinth and control methods, visit the Agricultural Research Council Website: www.arc.agri.za