Aqueous herbicide concentrates containing an auxinic herbicide, an aromatic ester, and, optionally, a surfactant and uses of aqueous herbicide spray mixtures incorporating such concentrates are described. The aqueous herbicide concentrates described herein include from 20 to 60 weight percent of a water soluble salt of an auxinic herbicide, from 0.1 to 20 weight percent of an aromatic ester, and, optionally, from 0 to 10 weight percent of a surfactant. The aqueous herbicide concentrate is a transparent, homogeneous liquid that forms an emulsion upon dilution into a spray solution.