The present invention provides novel compositions for use to enhance weed control. Specifically, the present invention provides for methods and compositions that modulate gene expression in johnsongrass. The present invention also provides for combinations of compositions and methods that enhance johnsongrass control. The invention comprises a method of Sorghum species weed control, in particular johnsongrass (Sorghum halepense) plant control comprising an external application of a herbicidal composition to a Sorghum halepense plant or a part of the Sorghum halepense plant in need of control, said herbicidal composition comprising a polynucleotide, an organosilicone surfactant concentration of about 0.2 percent or greater, and an effective dose of a nonpolynucleotide herbicide.