The Results of Herbicide Trials Conducted in the Cane Belt of Natal , 1962 / 63

Three herbicide screening trials, nineteen regional trials and three subsidiary trials were conducted during 1962-63, covering a wide range of environmental conditions and weed populations in the Natal cane belt. The outstanding herbicide was Paraquat which gave good post-emergent control of the two most important weeds, Cyperus esculentus and Panicum maximum, as wellas the majority of other weedspecies. The symptoms of severe cane leaf scorching observed after Paraquat applications soon disappeared, and ratings for cane vigour after three months showed Paraquat treated cane to be among the best. Paraquat is at present too expensive for field recommendations: Diquat gave fairly good control of most weeds except grasses; Dalapon was useful where grasses were the main problem; and DCMU gave good results where soil conditions were uniformly moist, whilst it also seemed to improve cane vigour. Of the remain. ing herbicides, CMU, Starn 34 and Kuron showed some promise, whilst Eptam gave such good control of Cyperus esculentus that further work with this chemical is planned to reduce or eliminate its depressing effect on sugarcane.