There is also occasional bleeding from the natural migration of resin or pitch, which may appear on the surface as beads of clear or colored resin exudate. This generally is limited to woods dried at temperatures too low to evaporate lighter components of the pitch. It is common in resinous species such as pines and douglas fir, and other soft woods especially around any wound areas. Resin or pitch bleeding typically occurs on surfaces warmed by sunlight or other sources of heat. Each bead or streak is from an individual resin canal and will appear as scattered discrete deposits. Stains appearing in larger areas may be the result of wounds that occurred in the living tree. Pitch exudations can be removed by using mineral spirits, however there is a strong possibility that pitch exudation will reoccur.