Wooden decks will become more vulnerable to mold and mildew growth over time. Green and black colored mold becomes noticeable when it penetrates into the wood over time making it more difficult to treat. To clean both composite decking material and wood, MJS Power Wash Solutions LLC uses a low pressure and cleaning solution method to treat the mold. Once treatment is completed, a higher pressure is used to bring the deck back to its original color. After drying we do recommend a stain and sealant for wood decking.