Why do some firewood species produce more smoke?

High Moisture Content

Firewood species with high moisture content, typically above 20%, tend to produce more smoke when burned. Trees like eucalyptus, poplar, and aspen often have higher moisture levels, which can lead to increased smoke production. Properly drying firewood to 20% or lower moisture content significantly reduces smoke production.

Volatile Compounds

Certain firewood species, such as pine and spruce, contain higher levels of volatile compounds like terpenes and resin acids. These compounds can ignite more easily, producing a greater amount of smoke. Burning firewood species with lower volatile compound levels, like oak and maple, typically results in less smoke production.

Drying and Stacking Techniques

To minimize smoke production, it’s essential to properly dry and store firewood. Stacking firewood in a way that allows for good air circulation, often in a crisscross pattern, can help speed up the drying process. Covering the top of the stack with a tarp or plastic sheet can also help retain moisture. Regularly checking and turning the firewood every few months helps to prevent mold and mildew growth, which can also contribute to smoke production.