Portland, Maine — Kevin Karnan looks for bicycle spokes every time he inspects firewood. If he can't find many, then he won't buy. Everyone should be that fussy, he says. Karnan sells wood stoves for a living - high-quality, high-priced, Norwegian imports that do a remarkable job of heating a home, given the right fuel. But, just as you wouldn't knowingly put water-contaminated gasoline in your car, you shouldn't put unseasoned wood in your stove, he says. Not, that is, if you want your money's worth in warmth and comfort.
That's where the bicycle spokes come in. Along with a few other telltale signs, they show you when the wood is adequately seasoned.
After felling, logs slowly dry out. As they do they shrink and crack; or check marks, as they are termed, appear. These tend to radiate out from the center like so many bicycle spokes and indicate when the wood is dry enough to burn.
Apart from the check marks, there are other ways to select seasoned firewood (don't go by check marks alone as a few will begin to show up in partially seasoned wood). Look for these signs:
* The bark. It should peel or break off easily. Soon after felling, the moisture beneath the bark's surface glues the bark tightly to the wood. By the time the wood has seasoned, however, this bond breaks down and the bark comes off easily.
* Dark ends. They should appear dark and obviously weathered.
* No green cambium. Cut back the bark to the cambium (that part of the bark immediately next to the wood). If there is any hint of green, the wood is still too fresh to burn.
* Weight. Pick up a log and feel its weight. Dry wood is much lighter than wet wood.
* Smell. Green wood smells green and sappy while dry wood does not.
Half-dry wood also has no smell just as it can have a few check marks. The idea, then, is never to rely on one indicator alone when looking and paying for seasoned wood.
All the foregoing does not mean that green wood should never be bought. If you have the space to store it for six months or more and the price is some $20 to $25 less than the going rate for seasoned wood, then it is a worthwhile buy.
In a pinch you can also burn green wood in your stove, given enough dry kindling to get it going. But it will not burn as hot because some of the heat is used to drive out the moisture before the wood will burn. Green wood is also more likely to coat your chimney with creosote.
All wood enjoys the same heat-to-weight ratio. A pound of white pine or aspen , for instance, will give you as much heat as a pound of hickory, the best of all stove woods. But it takes up twice the space. Where enough hickory to meet your needs might be stored comfortably in the garage, the aspen would spill out all over the driveway.
The hardwoods - hickory, apple, oak, or maple - burn with short flames and produce the lasting coals that are particularly useful in cook stoves. In contrast, the lightweight woods burn with a longer, hotter flame but do not last as long. In other words, soft woods will give you a hotter fire that needs more tending.
A good fire, say experts in the field, often comes from a blend of many different types of wood.