Pine does not cause creosote to accumulate in your chimney or stovepipe, contrary to popular belief. The following sections may provide you with the genuine answers to that issue: Pine has a greater sap content, but it is the actually fuel and generates heat.
What causes creosote buildup?
Some people may believe that pine firewood leaves more residue build-up, known as creosote, than hardwood because of the sticky, gum-like resins it contains. This is not true, according to research.
What really causes creosote to build up?
The condensation of combustible particles in the exhaust flue gas (smoke) is called creosote.
The cause of creosote condensation is the temperature of the chimney flue where the gas goes up. The hotter the better.
If the surface temperature of a flue is chilly, it will solidify the vaporization of carbon particles in the flue gas (smoke). Like hot breath on a cold mirror. This condensation forms creosote. If you're using wood that's been rained on or is still green, the fire will generally smolder and help create Creosote along the chimney lining.
When researchers wanted to find out which type of wood produced the most creosote in a wood fired fireplace, they tested it back in the early 1980s. The findings were perplexing. Contrary to popular belief, hardwoods like oak and madrone created more creosote than softwoods like aspen, fir, and pine.
Because the softwoods are dry, they produce a hotter and more intense fire. The hotter the fire the hotter the flue gets and therefor there is less of a chance to create Creosote. The faster air rises using the hotter fire's draft, quickly it traveling up the chimney! Because the flue gas doesn't have as much time to condense as creosote in the chimney, it does not cool down as fast.
"Fir creates more creosote than oak" isn't quite correct!
It's a misconception to believe that the pitch in the wood is what causes creosote. It's not the pitch that's causing the problem; it's those pesky water molecules. Once the water in the wood has evaporated, that pitch becomes high-octane.
Hint: "burn sappy-dry wood and create less creosote" Namely Softwoods