A.Charlie Jourdain responds: To remove a mild case of mildew, scrub the surface with a mild cleanser or non-ammonia detergent. Then rinse with household liquid bleach to kill the mildew spores. Finally, rinse with water.
For more severe mildew infestations, scrub the wood with a stiff bristle brush, using a solution of one cup trisodium phosphate, one cup liquid bleach, and one gallon of warm water. (Wear rubber gloves!) After scrubbing, rinse with a solution of four ounces oxalic acid crystals dissolved in one gallon of warm water in a nonmetallic container....
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