Agricultural Research Council, Plant Protection Research Institute, P.O. Box 318, Uitenhage 6230, South Africa
Viljoen, B.D., Agricultural Research Council, Plant Protection Research Institute, P.O. Box 318, Uitenhage 6230, South Africa; Stoltsz, C.W., Agricultural Research Council, Plant Protection Research Institute, P.O. Box 318, Uitenhage 6230, South Africa
European gorse (Ulex europaeus L) is a persistent, declared weed (Category 1) of South Africa. Current distribution is limited to the moist, high altitude regions of the Drakensberg (KwaZulu Natal Province) and Amatola (Eastern Cape Province) mountains. Gorse poses a threat to the plant diversity of forests, where it could establish itself quickly and occupies the site indefinitely. Once established, gorse can be difficult to eradicate, as it resprouts if cut or burnt and no herbicide was registered in South Africa at the time of this research on its control. The objective of this investigation was therefore to evaluate selected herbicides at various concentrations using different application techniques. Picloram and triclopyr ester proved the most effective and consistent across all application methods, while imazapyr is also recommended for cut-stump treatment. As a result of this research, both picloram and triclopyr were registered under Act 36 (1947) for the control of European gorse by means of cut stump and foliar treatment.