A steam sprayer for delivering steam onto and beneath a field surface is provided. The steam sprayer comprises a support frame having a plurality of steam spraying nozzles mounted thereto and oriented substantially downwardly for spraying steam onto and beneath the field surface. At least a steam generator is connected to the steam spraying nozzles for providing steam thereto. A water heating tank is connected to each of the at least a steam generator for providing heated water at a substantially constant pressure thereto. Compressed air is provided to the water heating tank for pressurizing the water heating tank. Power is provided to the water heating tank and each of the at least a steam generator.