Tree sap

In detail

Tree sap and pitch are plant resins — mixtures of terpenes and resin acids — that flow when warm and cure to a hard, glassy deposit as their volatile fraction evaporates. That curing is what makes timing decisive. Fresh sap is soft and largely removable with a solvent; cured sap has bonded mechanically to the surface texture and often has to be softened before it will release at all. On vehicle paintwork the problem escalates beyond adhesion: sap left in sunlight contracts as it hardens and the acids in it attack clear coat, leaving a ring-shaped etch mark that remains after the deposit is gone and needs polishing rather than cleaning. The carpet institute puts pitch on the solvent branch, opening with a dry-cleaning type solvent before detergent and vinegar. The same principle governs everywhere: dissolve the resin, then deal with the residue. Heat helps by softening rather than by dissolving, so a cloth soaked in warm water laid over the deposit for a few minutes does more than scraping, which drags cured resin across a finish and scratches it.

What works

• Solvent treatment is effective against Tree sap Supported

Why

• Tree sap is explained by Solubility and polarity