The Garden Bug: Burning Christmas Trees
By Brenda Weaver
Real pine, spruce, or fir Christmas trees are NOT appropriate fuel for an indoor fireplace. They have a high amount of sap in their trunks and branches, which can create intense, unpredictable blazes that are difficult to control. Their needles burn quickly and produce lots of sparks, which are dangerous, and these trees also produce creosote when burning, which is a respiratory hazard. It's better to compost a real tree in the garden.
Source: www.advancechimney.com