[1] Univ Cape Town, Dept Biol Sci, Rondebosch, South Africa
[2] Univ Western Cape, Dept Biodivers & Conservat Biol, Bellville, South Africa
[3] Univ Western Cape, Agr Res Council, Anim Prod, Bellville, South Africa
[4] Overberg Renosterveld Conservat Trust, Napier, South Africa
[5] Murdoch Univ, Ctr Rhizobium Studies, Murdoch, WA, Australia