Wood is the oldest fuel, yet we probably know less about burning the stuff than we do about newer fuels, including the nuclear ones.

Many myths have grown up around the burning of wood. Some of the best research on the subject is being done at Auburn University's Woodburning Laboratory. Here are some myths they've refuted:

"Pitchy, resinous woods such as pine create much more creosote in your chimney than the hardwoods." This truism simply isn't true. In fact, the hardwoods may create more creosote than resinous softwoods. Hardwood, often heavier than softwood, gives more heat per cord, not per pound.

"Wet, green wood creates more creosote than properly dried wood." Again not so. This doesn't mean green wood is as good as dried wood. Green wood gives less useful heat (as much as 44 percent less) than seasoned wood. Much of the heat is wasted boiling off water in green wood.

"Secondary air helps burn off volatile gases and thus reduce creosote production." It may be true in the early stages of a wood fire, but the secondary air may actually promote creosote production by cooling flue gases. This contradicts the theory that introducing secondary air (extra air above the fire to provide more oxygen for complete burning in a wood stove) is a creosote fighter.

"It takes at least a year to air dry wood. Two years are even better." Don't wait that long. Wood cut and split in the spring will be almost fully dried by heating season. The smaller you split it, the faster it dries. And shorter logs dry faster.

"The efficiency of wood stoves varies tremendously from brand to brand." Not true. Most good wood stoves have just about the same efficiency. Sophisticated intake systems and provisions for secondary combustion seem to have little effect. The most important factor is the ability to transfer heat from inside the stove to your home.