Published online by Cambridge University Press: 12 June 2017
Mixtures of CDAA + atrazine or propazine applied pre-emergence gave excellent grass and non-grass weed control and no sorghum injury. Such mixtures offer promise of more consistent weed control than either component alone and less soil residue than a higher rate of atrazine or propazine alone. CDAA + trichlorobenzyl chloride preemergence was a less effective mixture but gave better grass weed control and poorer non-grass control than propazine or atrazine pre- or postemergence. Atrazine or propazine postemergence following CDAA preemergence gave excellent results. The best time to spray sorghum with atrazine or propazine between planting and the 11-leaf stage was when the weeds were in the very early postemergence stage. Sorghum was tolerant at all times of application. Atrazine over all trials averaged superior to propazine as an herbicide for grain sorghum.