Cork bush (Mundulea sericea): This is a semi-deciduous shrub or small tree that grows up to 3m high from Windhoek and other central regions of Namibia, north through Damaraland and Kaokoland to Epupa Falls, to the Kavango River region, Tsumkwe and Kaudom Game Park and the Zambezi Region (formerly the Caprivi Strip). During the rainy season small bushes often line the roadsides around Etosha National Park.
The corky, deeply grooved bark is a beige-grey colour, the leaves a beige with a silky outer. The silver-green bicoloured leaves turn orange and red-brown at the end of the summer. The violet to mauve flowers are rain dependant and bloom from October to May. Drooping clusters of fruit pods are yellow-brown.
The common name of the cork bush is 'visgif'. This is derived from the crushed bark and roots which contain an extremely toxic glycoside used to poison fish. It has an immediate effect and causes the fish to float to the top where they can be caught easily. Locals claim this poison has even poisoned crocodiles. The leaves are poisonous to insects but are sometimes browsed on by game and livestock. The Natal Bar and Dusky Blue butterflies are attracted to this plant. The cork bush is drought resistant and frost hardy.