An aqueous suspension concentrate containing: (a) a first active ingredient comprising one or more triazolopyrimidine, triazolone, pyrazole or oxazole herbicides； (b) optionally, a second active ingredient, (c) a dispersant comprising a comb polymer； (d) a nonionic, alkoxylated surfactant or a block copolymer surfactant, and (e) optionally, a re-dispersing agent, wherein said aqueous suspension concentrate exhibits an acidic pH within the range from about greater than about 2 to about 4.
