Find out exactly how many cords of wood you need to get through winter.
Freshly cut green wood contains 40–60% moisture by weight. That water must be driven off before any heat can be extracted — which is why green wood hisses, smolders, and produces far more smoke and creosote than seasoned wood. Burning green wood wastes a huge portion of the wood's potential heat output on evaporation. A wood stove burning wet wood also runs at lower temperatures, which dramatically increases creosote buildup in the flue and chimney — the leading cause of chimney fires. The goal for any firewood before it goes into a stove or fireplace is a moisture content below 20%, with under 15% being ideal for high-efficiency stoves. You cannot reliably judge moisture by look or feel alone — a pin-type moisture meter ($15–25) is the only accurate way to know if wood is ready to burn.
The time required to season wood depends heavily on species, split size, and storage conditions. A round log (unsplit) can take 2 to 3 times longer to season than split wood of the same species, because the bark acts as a vapor barrier that slows moisture migration. Splitting wood exposes the porous end grain and inner wood surfaces to air circulation, dramatically accelerating drying. Generally, hardwoods like oak, hickory, and maple need 12 to 24 months to reach ideal moisture content when split and properly stacked. Softer, lower-density woods like ash, birch, and cottonwood can season in 6 to 12 months. The best approach is to cut and split your wood at least one full year before you plan to burn it.
The minimum seasoning time for most hardwood firewood split to 4 to 6 inch widths is 6 months, but 12 months is a far more reliable target for species like oak, hickory, and locust. Dense hardwoods with tight grain can take 18 to 24 months to fully season from green to under 20% moisture content. Softwoods like pine, fir, and cedar season faster — often 3 to 6 months — but also burn faster and produce more creosote if not fully dried. The single most reliable indicator of seasoning progress is a moisture meter reading, not the appearance of the wood or how long it has been stacked. Wood that has been stacked in a covered, well-ventilated location with the split face exposed to sun and prevailing wind will season significantly faster than wood in a shaded, poorly ventilated pile.
The target moisture content for firewood ready to burn is below 20%, measured as a percentage of the wood's wet weight. Most seasoning guides use 20% as the cutoff between "seasoned" and "not ready," with 15% or below being ideal for EPA-certified high-efficiency stoves that are designed to run hot and clean. Wood above 25% moisture will still burn, but it burns inefficiently, produces more smoke, generates more creosote, and delivers significantly less usable heat. At 50% moisture (freshly cut green wood), roughly half of the combustion energy goes toward evaporating water rather than heating your home. Use a pin-type digital moisture meter — insert the pins into a freshly split face for an accurate reading. Bark or weathered surfaces give false low readings.
Without a moisture meter, there are several indicators that suggest wood has seasoned, though none are as reliable as an actual moisture reading. Well-seasoned wood tends to be noticeably lighter in weight than green wood of the same species and size. The cut ends will show radial cracks or checks that radiate outward from the center — these form as the wood shrinks and dries. The wood will produce a clear, ringing "clunk" sound when two pieces are knocked together, rather than the dull thud of green wood. The bark on seasoned wood tends to peel away more easily and may already be loose or falling off. The wood's color lightens and the surface takes on a grayish, weathered appearance. Any of these signs suggest the wood is likely dry, but a $20 moisture meter removes all the guesswork and is well worth the investment for anyone heating with wood.
Yes — splitting is one of the most impactful things you can do to accelerate seasoning. Bark is highly resistant to moisture transmission, which is why unsplit rounds can take two to three times as long to dry as split pieces of the same diameter. Splitting a round exposes the porous inner wood (particularly the end grain, which dries many times faster than the face grain) to air, sun, and wind. The smaller the split pieces, the faster they dry — but you also want pieces large enough to provide a sustained burn once they are seasoned. A practical split width of 3 to 6 inches balances fast seasoning with good burn quality. Splitting immediately after felling is always preferable to leaving rounds to sit — green wood is much easier to split than wood that has partially dried and hardened.
Among common firewood species, ash is widely regarded as the fastest to season and the easiest to work with. Ash has an open, porous grain structure that allows moisture to escape quickly, and many experienced woodcutters claim ash can be ready to burn in as little as 6 months from felling. Birch and poplar (cottonwood) also season relatively quickly — typically 6 to 9 months for split pieces. By contrast, oak, hickory, and black locust are among the slowest to season because of their dense, tight-grained structure. A freshly split piece of white oak may take 18 to 24 months to drop below 20% moisture even when stored correctly. The trade-off is that slow-seasoning dense hardwoods deliver far more heat per cord than fast-seasoning softwoods, making them worth the wait for home heating applications.
The ideal storage keeps the top of the stack covered to block rain and snow while leaving the sides open for maximum airflow. A simple lean-to roof or even a tarp draped over the top (not wrapped around the sides) is sufficient. Covering the sides traps moisture and humidity around the wood, which actually slows drying and can encourage mold growth. The wood must be stacked off the ground — on pallets, pressure-treated lumber runners, or concrete blocks — to prevent ground moisture from wicking up into the bottom layer and to allow air to circulate underneath. Orient the stack so the prevailing wind and afternoon sun hit the cut ends of the wood, since end grain dries 10 to 15 times faster than face grain. Avoid stacking firewood directly against the house or barn — it provides ideal habitat for termites, carpenter ants, and mice.