Not all trees offer the same type of firewood to burn in a fireplace. Burning hard wood vs. soft wood, or seasoned vs. unseasoned will produce fires that vary in heat intensity, smoke production and the ambience factor of snapping and crackling.
Unless it has been dead for some time, when a tree is first cut down, it contains a lot of moisture. Fresh wood is called "unseasoned." Moisture in unseasoned wood will make it more difficult to light and will cause the wood to smoke. If the flame goes out on unseasoned wood, the wood will continue to smoulder. Smouldering wood adds an unpleasant burnt smell to the house and creosote to chimney. To avoid this issue, the wood should be seasoned.
Cut, split and stack wood outdoors to dry or "season." Drying occurs more quickly when the wood is stacked with every other row turned 90 degrees, which allows air to circulate better between the logs. Wood is best dried in a shed, away from rain. If you do not have a shed, cover the split wood with a tarp to keep rainfall off the wood. Remove the tarp on sunny days so moisture can escape, or better yet, use the tarp in a tent-fashion, suspended over the wood stack.
Appearance of Seasoned Wood
You can tell the wood is dry from the hollow the sound that is made when you knock two pieces together. Seasoned wood is also cracked, grey in colour and much lighter without the water content. Wood for a fireplace needs at least one year to dry before using. Seasoned wood generates the most heat and burns clean, with less smoke that unseasoned wood.
If you are buying seasoned wood, it will be sold by the cord or half cord. A cord measures 8 feet long, 4 feet high and 4 feet deep. Seasoned wood will cost more than unseasoned wood.
Deciduous trees like eucalyptus, madrone, oak and walnut as hard woods are the best choice if you want to produce a lot of heat. Ash, locust, hickory, apple, plum, cherry, pear and ash come next, putting off slightly less heat. Apple, pear, plum and cherry woods offer a fruity scent as they burn. Maple, sycamore and elm are fair for heat production, while cottonwood, alder and willow are poor choices for heat production.
As seasoned wood, all hard woods will burn longer than soft woods, giving off continuing heat and ambience. Hard woods tend to be more difficult to start burning. A small amount soft wood, which is easier to light, along with some clean newspaper make good kindling for starting a hard wood fire.
Conifers are soft wood with pine and fir suitable for burning. Fir gives off a delightful scent, reminiscent of the holiday season. Cedar gives off a pleasant scent and it snaps and crackles as it burns.
As seasoned wood, conifers burn hot but they burn fast. If you want long lasting fire, you will need to continue to add more wood. Seasoned fir can be used as kindling to get hard woods to start burning.