The resin we extract from a natural pine tree is often called "pitch" but when pure it is actually only natural resin. It is the sap - the blood circulating inside the tree. When a pine tree bark is wounded it segregate the resin in an effort to protect and heal it-self.
The resin can be collected taking advantage of an existing wound or provoking it. Provoking the wound allows to collect practically pure resin but can causes strain on the tree it-self. Collecting it from an existing would is suited to make "pitch" as during the healing tprocess the resin mixes with chunks of bark.
I collected the resine on a "pino carrasco" tree in the south mediteranean face of the Montseyn mountain of Catalunya. I choose a tree with a strange bend of the trunk. I chopped the bark off tnclination of the trunk, the sap will drips to the groulnd. Nailed a thin foil to the edges of the "scar" in a funne shape so to direct the liquian attached thin can. In 24 hours I collected around 75ml. od pure resin. To figure out the quantity on a longer time scale I replaced the thinfoil (too fragile) with a plastic cloth and left it to drip for a few weeks. (drip starts: 21 june)