Damp wood should not be used in a fireplace. According to the Chimney Safety Institute of America, burning wet wood can cause odor problems and issues with smoke. It rapidly deposits creosote in the chimney, increasing the risk of a chimney fire.
Wood is wet when the moisture content is more than 25 percent. Freshly cut wood typically has 80 percent moisture and requires a full year to become seasoned, which means it contains 20 to 25 percent moisture content. When damp wood is burned, a fire is difficult to start and hard to maintain. It creates a hissing sound as water boils out of the wood. A fire made with damp wood also releases gallons of acidic water in the form of creosote, depositing it in the chimney. This residue can cause a chimney fire if the residue is not cleaned out on a regular basis.