When looking online you might see articles telling you not to burn pine in wood stoves because of the excess buildup it creates in the stove pipe or flue. Ideally, your firewood supply should contain a mixture of both hardwoods and soft woods but all wood creates buildup in stove pipes. Dense hardwoods burn longer and produce more heat, making them superior to softwoods for maintaining your fire. Pine certainly isn’t the best wood to use in stoves but sometimes it’s all that available.
When you burn wood in a stove, creosote collects in the stove flue. Creosote is nothing more than a condensation of small, unburned particles contained in the smoke that coats the chimney surface as it exits. When the heated particles contact the cooler flue, the vapor solidifies into a layer of creosote. Since pine burns much faster, with less BTUs than hardwood, people often load up their stoves and choke the air down to make them burn longer. Doing this reduces the speed the smoke travels through the flue. Its this smoldering effect that actually produces more creosote.
You can reduce the amount of creosote by properly seasoning your firewood. When your firewood is dry -- about 20-percent moisture or aged at least six months, if not more, it will burn more efficiently, creating less creosote. Green, wet wood smolders, creating more creosote-producing smoke which represents nothing more than energy literally going up in smoke. Burning a hotter fire and using smaller logs -- no matter what firewood you use -- also helps avoid excessive creosote. In addition, don't burn treated pine lumber nor any other piece of trash.
Creosote is highly flammable and can lead to house fires. Clean your chimney at least once a year, more often for heavy use, to remove inevitable accumulation.