DOUGLAS FIR: Medium heating value, doesn’t make too much ash. Probably the best conifer for firewood — better than some of the hardwoods. An older tree or tight-grain Douglas fir is easy to split, but some of the younger, second growth can be extremely difficult.
RED ALDER: Seasoned alder burns warm but fast. Wet alder puts out a lot of ash and very little heat. Cuts and splits easily with an ax. Fir and alder are competitively priced.
LODGEPOLE OR PONDEROSA PINE: Lodgepole burns hot and fast, and splits easily. Ponderosa from the west side of the Cascades burns hot and fast but may be difficult to split and be full of pitch.
OAK: Properly seasoned oak holds a fire, doesn’t spark and splits pretty well. But it doesn’t produce much heat and will make lots of ash if not adequately seasoned.
OREGON ASH: Wet or dry, ash will produce a decent fire, but with a lot of ashes. Most ash splits relatively easily as long as it is still green.
BIGLEAF MAPLE: Close to the quality of ash and has similar splitting characteristics. Burns slightly cleaner, sparks a lot more and doesn’t heat quite as well.
MADRONE:When seasoned, this hard, dense wood burns very hot and produces long-lasting coals. Some madrone is knotty and hard to split. It’s expensive, but a little goes a long way in heating.
— Oregon State University Extension Service