9 Things You Should Never Leave Out in Your Yard

3. Oily Rags

Paige NeJame, owner of CertaPro Painters in Boston and the South Shore of Massachusetts, cautions against leaving oily rags from painting and staining projects in your yard. “When oily rags in a pile start to dry and heat up, oxygen gets trapped inside,” she says. “The mixture of oil, heat and oxygen can cause a spontaneous combustion.”

The National Fire Protection Association recommends disposing of flammable oily rags by first hanging them outdoors in order to let them dry. Once they are dry, put the rags in a water and detergent mixture before disposing of them in a hazardous waste collection drive.