The status and population structure of the marula in the Kruger National Park

The South African National Parks identified the need for autecological studies on specific rare indicator keystone plant species. The marula is one of the preferred tree species particularly selected for by elephant and whose current damaged condition and disappearance in a mature state in the Kruger National Park is causing serious concern. The density of marula trees and the current population structure of this tree species were examined in four major landscapes of the Kruger National Park. Results indicate that the marula population in the Colophospermum mopane shrubveld has become virtually extinct, while the Colophospermum mopane/Acacia nigrescens savanna has a markedly unstable population with a lack of immature trees. The marula populations in the southern landscapes (mixed Combretum/Terminalia sericea woodland and Sclerocarya birrea/Acacia nigrescens savanna) appear to be healthy. The population structures on the different substrata (granite and basalt) differed significantly. Results of this study further indicate that diversity of vegetation plays an important role in determining herbivory pressure, and consequently in influencing the marula population structure.