Pesticidal concentrate with stabilizing agent

A pesticidal concentrate comprising o-isopropoxyphenyl methylcarbamate and citric acid or a salt thereof dissolved in a liquid water soluble dispersion medium selected from the group consisting of methanol, ethanol, isopropanol, dipropylene glycol monomethyl ether, and polyethylene glycol, the amount of the dispersion medium being sufficient to assure dissolution of substantially all of the carbamate at room temperature and, the amount of the citric acid or salt thereof being sufficient, when the concentrate is diluted to result in a pesticidally effective amount of the carbamate with water, to result in an aqueous solution having a pH of 7.0 or less.