Georgia and other Southern states were once the center of the turpentine industry due to the huge swathes of pine trees. It was called the naval stores industry because pine tar was used to seal ships. Turpentine is used to make paint and paint thinner, and pine resin, or rosin, makes a violin bow sticky enough to create sound, and makes ballet slippers not slippery. Pine sap products are also used in Pine Sol, Vicks' VapoRub, cosmetics, and even chewing gum. Collecting the gum from pine trees first involved cutting a box into the tree to collect sap, but that destroyed the tree. In 1901, a new method was developed that involved making diagonal slashes in only part of the tree, and collecting the gum in an exterior box or bucket. Trees survived this method to be harvested again. The slashes resembled a cat's whiskers, so the scars from a sap harvest are called catfaces.
The pine sap is distilled to make spirits of turpentine, and what's leftover is the rosin. You can still see the process of distilling turpentine at the annual Catface Turpentine Festival in Portal, Georgia, every fall. Portal has one of only three operating turpentine stills left in Georgia, and they show it off to the public during the festival, which is scheduled for October 5th this year.
This deep dive into the turpentine industry came from a post about rosin baked potatoes, which are actually potatoes boiled in rosin. Boiling rosin reaches a much higher temperature than water, and cooks the potatoes much faster. But you can't eat the skin! You'll find more links about the potato recipe at Metafilter.
(Image credit: Jud McCranie)