Affiliation: | 1. Department of Botany, University of Pretoria, Pretoria, 0002 Republic of South Africa;2. Department of Vegetation Science & Plant Ecology, Agricultural University, Bornsesteeg 69, NL-6708 PD Wageningen, The Netherlands;3. DLO Institute of Forestry & Nature Research, PO Box 23, NL 6700 AA Wageningen, The Netherlands;4. Department of Botany, University of Natal, Private Bag X01, Scottsville, 3200 Republic of South Africa |