Burn seasoned hardwood below 20 percent moisture. Everything else on this page is detail. Oak, ash, hickory, maple and birch burn longest and leave the best embers. But the species argument is the one firewood conversation people have, and it is the less important one: a dry softwood fire beats a damp hardwood fire comprehensively, every time, on heat, on smoke and on how easily it lights.
Moisture is the whole game
The EPA’s Burn Wise guidance states plainly that wood burns best at a moisture content of less than 20 percent. Above that figure, a meaningful share of the energy in the fire goes into boiling water out of the log instead of warming you, and the water leaves as the white smoke you spend the evening dodging.
That is also why people are disappointed by smokeless pits. The double wall preheats secondary air and feeds it back above the fire to burn off smoke particles — but only once the firebox is properly hot, and a wet log never lets it get there. The pit is working as designed; the fuel is wrong.
You cannot judge this by eye, and almost everyone overestimates how dry their wood is. A pin-type moisture meter costs about thirty dollars. Split a piece and test the fresh face— the outside of a log that has sat in the rain and then dried reads low and tells you nothing about the middle.
Hardwood vs softwood, honestly
Hardwood— oak, ash, hickory, maple, beech, birch — is denser, so a given volume holds more energy. It burns longer, produces a deep bed of embers that keeps radiating after the flames drop, and throws fewer sparks. It is also slower to season: dense splits can take a year or more to get under 20 percent.
Softwood— pine, spruce, fir, cedar — lights easily, burns hot and fast, and seasons quickly. It also spits and throws more sparks because of the resin, which matters if your pit is near decking or dry grass and is a good reason to run a spark screen. The common warning that you should never burn pine is really a wood stove and chimney concern about creosote; in an open outdoor fire pit, dry softwood is perfectly usable fuel and excellent kindling.
The practical answer for most people is both: softwood to get the fire established quickly, hardwood once it is going, so the evening settles into a long bed of embers rather than a series of bright short bursts.
What never to burn
The EPA lists these as materials to keep off a fire entirely, and the reasons range from toxic smoke to simply ruining the fire:
- Household trash, including cardboard, plastics, foam and the coloured ink on magazines, boxes and wrappers
- Coated, painted and pressure-treated wood
- Ocean driftwood, plywood, particle board, or any wood with glue on or in it
- Wet, rotted, diseased or mouldy wood
- Plastic, asbestos, rubber, manure and animal remains
Pressure-treated timber and painted wood are the two that catch people out, because an offcut from a decking job looks exactly like firewood. Driftwood is the other: the salt in it releases harmful compounds when burned. And never use petrol, lighter fluid or any accelerant to revive a fire — use a proper fire starter, which also saves you sitting in the smell of it all evening.
Buying wood, and what the labels mean
Kiln-dried is the premium option: dried in a kiln to a guaranteed low moisture content, usually well under 20 percent, and it costs accordingly. It is the right buy if you have nowhere to season wood and want a smokeless pit to actually behave.
Seasonedis an unregulated word. It is supposed to mean air-dried for six months or more, which is what the EPA recommends, but it frequently means “cut six months ago and left in a heap.” Check it with a meter when it arrives; a reputable supplier will not mind.
Green or freshly felled is cheap and unusable this year. Buy it only if you have a rackand the patience to season it yourself — off the ground, top covered only, which is the EPA’s own method and is set out in how to season firewood.
One last thing worth knowing: don’t move firewood long distances. Transporting wood across regions is a well-established route for spreading tree pests and disease, which is why many states and parks ask you to buy local and burn local. It also happens to be the cheaper option.
