Use of Ammophila arenaria for dune stabilization in South Africa and its current distribution - Perceptions and problems

This paper examines the use of the European dune pioneer plant Ammophila ar enaria (marram or European beach grass) for dune stabilization in South Afr ica in the past and present, its present distribution in South Africa, and the perceptions of coastal management agencies and the public about its fur ther use. The planting of A. arenaria became the most important means of du ne stabilization, by human intervention, along the South African Cape coast in this century. Its modern distribution from the semiarid west coast to t he subtropical shores of the Eastern Cape extends through various climatic zones. Although historical data are missing for some areas, there is no ind ication of its unaided spread. A. arenaria occurs at most sites because of its prior planting. The South African climate appears to affect its vigor. However, concern about the use of the alien grass has been raised since it has proved to be a highly invasive species in other parts of the world, par ticularly along the North American west coast and in Tasmania. While the CS IR (Council of Scientific and Industrial Research) promotes its use, CNC (C ape Nature Conservation) follows a policy that restricts the use of any ali en plant, including A. arenaria, and requests further research on its invas ive properties. Although a questionnaire survey shows that stabilization si tes featuring large areas of A. arenaria are accepted by the South African public, current coastal management practices need to be analyzed critically . A thorough investigation of the potential invasiveness of A. arenaria on South African coastal dunes will be essential and shed new light on the Ame rican A. arenaria problem.