Some people burn wood to save a few bucks. Others relish the atmosphere of a crackling fire. Still others burn wood to rid their property of unwanted or blown down trees.
Quality firewood is a loaded term. Many factors are involved. In general, hardwoods are denser and contain more energy than softwoods. However, it’s definitely not that simple and I always like to keep some softwood logs handy. Dry softwood makes great kindling. It catches fire quickly.
Pines, cedar and cypress are examples of what we call softwoods. We call broadleaf trees hardwoods even though some are less dense than some conifers. Density of dried wood determines the amount of energy in firewood.
Many people claim it is unsafe to burn pines and other resinous trees in a woodstove or fireplace because they deposit creosote in the chimney. This is true if the wood is burned slowly and inefficiently. However, well-seasoned softwood and adequate oxygen will generate a fire that burns hot enough to keep this from happening. The wood contains resins but dry wood creates hot fires which burn efficiently and clean.
Proper seasoning is related to the amount of water in the wood. It should be as dry as possible. Dense hardwoods like oaks, hickories, and beech make great firewood but only if they are dry and solid. Green oak is far dirtier and produces less heat than dry pine.
Water must be boiled off and this is a costly process. When any wood burns at low heat more smoke is produced. Smoke is full of unburned particles and these collect in the flue. Smoldering fires are dangerous. At high temperatures the burn is cleaner. This is great, but not if thick deposits are already present in the chimney. It should be checked regularly.
How do we know if wood is seasoned properly? Seasoned wood will have many cracks on the ends and will probably display somewhat of a gray color. Whittling off a piece usually reveals a bright fresh color underneath. If it doesn’t or the wood shaves off too easily, then it might not be sound and that’s not good either. Punky (partially decomposed) wood may be plenty dry, but it doesn’t contain much heat.
Proper seasoning takes several months. Freshly cut wood is never worth burning right away. Even if the wood was cut down several months earlier, if it was only bucked into stove length pieces and split recently it should be considered green wood.
When properly seasoned, dense woods like oak, hickory and beech contain more heat than pines. For that reason they are preferred, especially at night when tending a fire is inconvenient. Most well-seasoned softwoods burn hot but they burn quickly.
I can’t stress enough that dry softwoods are safe if the stove or fireplace assembly is in good condition. They burn hot and clean. They don’t produce a good bed of coals which will provide heat for a long period of time, but they’re much safer and produce more heat than partially or unseasoned hardwoods. That’s a fact.
Ted Manzer teaches agriculture at Northeastern High School. (firstname.lastname@example.org)