Useful plants of Namaqualand, South Africa: A checklist and analysis

Abstract

A comprehensive checklist of 2902 vascular plant species for Namaqualand (Western and Northern Cape Provinces of South Africa) is presented, in which the local traditional and contemporary human uses of 384 taxa are indicated. Information was obtained through a literature study and extensive field survey work, including rigorous and detailed interviews and field walks. Of the total of 383 useful plant species, 240 are used in traditional medicine, 185 are edible, and 216 are used in crafts and other miscellaneous uses. Several species are used in more than one of the three main use categories. A total of 119 vascular plant families is represented in Namaqualand, of which 78 include species that are used locally for medicine, food and crafts. Species from 66 families are used for medicinal purposes, 53 include edible species and 57 include species used for crafts and other miscellaneous uses. The families that contribute the highest numbers of useful plant species are Asteraceae (51 spp.), Geraniaceae (23 spp.), Aizoaceae (22 spp.), Apocynaceae (18 spp.), Iridaceae (17 spp.), Asphodelaceae (13 spp.), Fabaceae (13 spp.), Lamiaceae (11 spp.), Apiaceae (10 spp.) and Amaryllidaceae (9 spp.). There are 45 new species-records of plants with human uses and 147 newly reported uses (38 medicinal, 51 edible and 58 crafts and miscellaneous uses). The checklist was used for a regression analysis of the total number of available plant species per family (as independent variable) and the total number of species per family that are used in Namaqualand (as dependent variable). Residual values of predicted vs actual numbers of species show an over-representation of especially Asteraceae (+21), Geraniaceae (+16) and Apocynaceae (+11) and an under-representation of Aizoaceae (−17), Hyacinthaceae (−7) and Poaceae (−6). The inventory data and results are not only of importance in understanding the broader plant use patterns of the Khoi-San legacy in the Succulent Karoo Biome, but also contribute to the conservation of the cultural heritage of the people of Namaqualand, and as a source of ethnobotanical data for future research and comparative analyses.