Tackle wax stains and white marks from heat and moisture by laying a cotton cloth over the surface of the knotty pine table at the site of the stain. Warm your clothing iron on the lowest heat setting. Press the iron onto the cotton cloth for three to five seconds at a time to transfer the white marks or wax from the table to the cloth.
Dampen a cloth with white vinegar. Wring out the cloth to remove excess vinegar. Wipe the surface of the knotty pine table to remove grease and oil stains.
Pour 1 gallon of warm water into a bucket. Add 1 tablespoon of wood soap to the water.
Moisten a microfiber cloth with the diluted wood soap solution. Wipe down the entire knotty pine table surface to remove dirt and caked-on stain matter. Rinse the cloth to remove stain material. Add more wood soap solution and continue to wash the surface.
Rinse the knotty pine table with a damp cloth. Dry the surface with another cloth to avoid moisture damage.
Apply a dab of white toothpaste to your fingertip. Rub the toothpaste in a circular motion on any remaining old stains on the knotty pine table. Wipe the toothpaste and stain material off with a damp cloth. Dry the table with another cloth.