When a tree is cut down, the wood is considered to be green because it has not yet been allowed to dry. It is also wet and cannot be used to build anything because it warps as it dries and needs to be cured in some way. There are two main drying methods, which are kiln dried and seasoned, and each offer different benefits for firewood.
The moisture content of seasoned wood is much higher than the kiln dried wood, which leads to many issues. The first is when the moisture content is higher, more energy is expended when the wood burns because of the evaporation of the moisture. This leads to more energy being expended drying the wood rather than offering the high heat that helps to keep a room warm.
Kiln dried wood is much drier and this lack of moisture means that there is less smoke when the wood is burning. It also offers a higher heat source because there is less energy being expended drying the wood. This also means that when kiln dried woods are used for construction, there is less chance of the wood warping.
Wood that has been dried in a kiln can burn faster than seasoned firewood because of the lack of moisture. This can be an issue for those who need their wood to last longer rather than burn hotter. Most of the wood that you can purchase at your local grocery store for barbeques, fireplaces, or wood stoves has been kiln dried.
When it comes to choosing the better wood for burning, seasoned wood is far and away the winner. The wood generally burns longer and produces more heat. For the homeowner that is trying to keep their home warm and costs down, this is a huge factor. If you are building something, you may want to look into finding the best possible source of kiln dried wood for your construction project.