Hemlock as Firewood: Heat Output and Growth Rate

Hemlock is fair firewood: low heat (15.9 million BTU/cord vs. oak's 30), many sparks, but pleasant aroma. Similar to pine. It grows 12–18 inches annually on good sites. Since your hemlocks are shading out desirable hardwoods, selective removal for firewood is reasonable, but expect modest heat return.

Consider mixing with denser woods for better burns. Always season 6–12 months.