Amanda T Lombard, Botany Department, Nelson Mandela Metropolitan University; Sustainability Research Unit, George Campus, Nelson Mandela Metropolitan University Richard M Cowling, Botany Department, Nelson Mandela Metropolitan University; Sustainability Research Unit, George Campus, Nelson Mandela Metropolitan University Jan H.J. Vlok, Sustainability Research Unit, George Campus, Nelson Mandela Metropolitan University Christo Fabricius, Sustainability Research Unit, George Campus, Nelson Mandela Metropolitan University |