Need to remove sap from asphalt? Get out the hand sanitizer.
Q: Our walkway is asphalt, and we sealed it about three years ago with the standard sealing material. This autumn, sap from a nearby pine tree dripped onto the walkway, leaving many white spots. How can we remove the spots without damaging the surface? We have tried using mineral spirits, with no success. Is there a product that can remove the dried sap spots?
A: The alcohol-based hand sanitizer that you may have stocked up on works wonders for removing pine pitch from almost any surface, and it won’t hurt asphalt or asphalt sealer. Sanitizing hand wipes with alcohol as their key ingredient should also work.
Alcohol should not damage asphalt, especially if it has been in place for a while, or asphalt sealer, said Chad Hopkins, lead estimator for AC Paving, a company in Millersville, Md.
Carol Chapin, vice president of research and development for Simple Green, which makes cleaning solutions, suggested wetting a cotton ball with acetone nail polish remover and dabbing that on the pitch to soften and remove it. Or, she said, you could use a petroleum-based hand cleaner, such as Goop ($9.99 for a 14-ounce tub on Amazon). After you apply either of these, she suggests you wash the surface with a solution of 10 parts water to 1 part Simple Green All-Purpose Cleaner ($4.97 for a 32-ounce bottle at Home Depot).
It’s also possible to use undiluted Simple Green to dissolve the pitch. This approach might save you from having to spot-treat every place where the pitch dripped. However, it’s important to test first to ensure you won’t damage the surface. Simple Green is a degreaser, and asphalt is a petroleum product. Depending on how the surface is sealed, the cleaner could break down the oil in the pavement.
“Changes in air-quality regulations have caused changes to the formulas of coatings such as asphalt sealers,” Chapin said via email. “Some are not as impervious to cleaners as they used to be.”
To test whether you can safely use Simple Green, soak a cotton ball or a sponge with the cleaner, and place it on the pavement in an inconspicuous area. After five minutes, remove the swab, and rinse the area thoroughly with water. Once it dries, check whether the spot has turned brown, and press with your finger to see whether the pavement is softer or pitted. If no change is evident, it’s safe to proceed.
The Simple Green website (simplegreen.com) details how to use undiluted Simple Green to remove tree sap from cars: Wash the surface. Apply the full-strength cleaner to a clean washcloth or terry cloth. Let the cloth sit on each spot for at least 30 seconds. Gently scrub with a soft-bristle brush or a nonabrasive scrubbing pad. Rinse.