Provided herein are synergistic herbicidal compositions containing (a) a compound of formula (I): or an agriculturally acceptable salt or ester thereof and (b) a protoporphyrinogen oxidase inhibitor, e.g., acifluorfen, azafeniden, bifenox, carfentrazone-ethyl-ethyl, flumioxazin, ipfencarbazone, oxadiargyl, oxadiazon, oxyfluorfen, pentoxazone, pyraclonil, pyraflufen-ethyl and saflufenacil, or a salt or ester thereof. The compositions and methods provided herein provide control of undesirable vegetation, e.g., in direct-seeded, water-seeded and transplanted rice, cereals, wheat, barley, oats, rye, sorghum, corn or maize, sugarcane, sunflower, oilseed rape, canola, sugar beet, soybean, cotton, pineapple, pastures, grasslands, rangelands, fallowland, turf, tree and vine orchards, aquatics, plantation crops, vegetables, industrial vegetation management (IVM) and rights-of-way (ROW).
