One of the most difficult kinds of odors to remove from clothing is that of smoke. Whether it is campfire or residue from a near by agricultural burn, this is an offensive smell that can stick around after several washes. Vinegar can be used to remove this smell, but usually not in the washing machine. Try filling up a tub or large sink with very hot water, then add half of a cup to a cup of vinegar. Run a clothes line above the body of hot water and secure your clothing to it. The steam from the water vinegar mix will help to remove the scent.