Black Flag 14 oz. Foaming Wasp & Hornet Killer. This non-staining aerosol spray delivers a blanketing foam to kill wasps, hornets, and yellow jackets by contact. It also controls carpenter ants, harvester ants, mud daubers, scorpions, spiders (including black widow and brown recluse), and tent caterpillars. The powerful jet spray shoots up to 20 feet for fast knockdown, allowing you to treat nests above ground from a distance. Apply to the nest outdoors at sunset when insects are less active, standing up to 20 feet away and slowly walking toward it while spraying. Treat until the nest is soaked and wait at least 24 hours before removing it. Remember to treat the nest, not individual insects. This formula leaves no oily residue and is non-staining to most home siding, depending on age and cleanliness. Test in an inconspicuous area and check in a few hours.