Firewood

What this is

Wood harvested, dried (seasoned), and burned as fuel. The species, density, moisture content, and form (split rounds, kindling, slabwood) all shape how the wood burns. This page is a hub for the trees of the vault that produce firewood — each tree entry declares produces: firewood with its specific BTU and burn character; the Produced by list below renders automatically.

How firewood is measured

The standard volumetric unit is the cord: a stack 4 feet wide × 4 feet high × 8 feet long, or 128 cubic feet of stacked split wood (~85 cubic feet of solid wood after subtracting the air gaps). Heat output is measured in British Thermal Units per cord (BTU/cord), and densities range nearly 3× between the lightest softwoods and the densest hardwoods.

Standard reference figures (millions BTU per cord, air-dried at ~20% moisture):

Highest-heat hardwoods (24–33 MBTU/cord)

• Osage orange — ~32.9 (highest of any North American firewood; intense, throws sparks)
• [[shagbark-hickory|Shagbark hickory]] — 27.7 (the classic eastern-US premium firewood)
• [[black-locust|Black locust]] — 26.8 (very high heat; long-lasting coals; foul-smelling smoke when green)
• Honey locust — 26.5
• Apple — 26.5 (excellent; aromatic when burned)
• [[mulberry|Mulberry]] — 25.8
• White oak — 25.7
• [[hornbeam|Hornbeam]] / American hophornbeam (“[[american-hornbeam|ironwood]]”) — ~27 (extreme density; almost impossible to split)
• Persimmon — 24.4
• Beech — 24.0
• [[sugar-maple|Sugar maple]] — 24.0
• Red oak — 24.0

Strong hardwoods (20–24 MBTU/cord)

• [[ash|White ash]] — 23.6 (splits beautifully; can be burned slightly less seasoned than most)
• Yellow birch — 23.6
• [[black-walnut|Black walnut]] — 22.2
• [[tamarack|Tamarack]] / larch — 21.8 (highest-BTU softwood; rivals weak hardwoods)
• Cherry / [[black-cherry|black cherry]] — 20.0 (aromatic; classic smoking wood)
• Elm — 20.0 (very hard to split — interlocked grain)
• [[sweet-gum|Sweet gum]] — 20.6
• [[birch|Paper birch]] — 20.3
• [[american-sycamore|Sycamore]] — 19.5 (hard to split)

Modest hardwoods and high-end softwoods (16–20 MBTU/cord)

• [[red-maple|Red maple]] — 18.6
• Hemlock — 19.3
• [[bald-cypress|Bald cypress]] — ~18
• Tulip poplar — 17.7 (fast burn; good kindling-grade)
• Red alder — 17.2

Softwoods (12–18 MBTU/cord)

• Spruce — 15.5
• Fir — 16–21 (varies by species)
• Pine (eastern white) — 14.3 (low BTU, fast burn, high creosote)
• Cedar / juniper — 13–18 (sparks; aromatic; valued for kindling and outdoor fires)

Splitting

• Splits cleanly (straight grain): ash, oak (when straight-grained), cherry, maple (most), beech (when fresh), birch, black locust
• Splits with difficulty: elm (twisted/interlocked grain — “the homesteader’s curse”), sycamore, sweet gum
• Nearly impossible to split without a hydraulic splitter: hornbeam (“ironwood”), osage orange (hardest North American wood)
• Splits easiest when frozen: most species, but particularly birch and red maple

Smoke, sparks, and creosote

• Heavy creosote producers (chimney-fire risk in poorly maintained flues): all softwoods — pine, spruce, fir, hemlock; also unseasoned hardwoods of any kind
• Heavy sparking: pine, spruce, juniper, cedar, hemlock — these throw embers and are unsafe for open hearths without a screen; fine in closed stoves
• Cleanest-burning: well-seasoned oak, hickory, ash, beech, sugar maple, black locust
• Aromatic/specialty smoke (for cooking and atmosphere): apple, cherry, hickory, oak (for traditional barbecue and smoking); cedar, juniper (for smudging and outdoor fire); birch (for sauna firewood in Finland and Russia)

Seasoning

Freshly-cut “green” wood is up to 50% water by mass and burns inefficiently. Seasoning — air-drying split wood under cover with airflow — reduces moisture to ~20%, the threshold for clean efficient combustion.

Approximate seasoning times (split rounds, ventilated stack):

• Pine and other softwoods — 3–6 months
• Most hardwoods (ash, birch, cherry, maple) — 6–12 months
• Oak — 18–24 months (oak’s slow drying is famous; rushing it produces hissing, smoking, inefficient burns)
• Black locust — 12–18 months (very dense; takes time)

Cut, split, and stacked off the ground with the top covered and the sides open. The split surfaces dry, not the bark.

Cultural and historical

Wood was the dominant home-heating fuel across all of humanity until coal began displacing it in industrial-era England (~1800), oil and gas displaced it across the developed world (~1950), and electricity continued the transition into the 21st century. In much of the rural global South, wood remains the daily cooking fuel; in cold-temperate regions across the developed world, wood is undergoing a revival as a sustainable supplemental heat source where managed woodlots are available.

Firewood traditions remain culturally deep:

• The Scandinavian ved — stacked firewood walls are an art form, photographed and competitively judged
• The Finnish sauna and the Russian banya — birch is the canonical sauna wood
• The American Appalachian and Ozark woodlot tradition — oak and hickory for the home stove
• The German Kachelofen and other masonry-heater traditions — slow-burning hardwoods in massive thermal-mass stoves
• The Mexican comal and South Asian chulha — wood and charcoal cooking on every household scale

Sustainability and the modern context

Burning wood is carbon-neutral on multi-decade timescales if the wood comes from sustainably managed forests where regrowth matches harvest. Coppicing and pollarding — cutting trees back to a low base or to the trunk so they regrow into multi-stemmed clusters — are among the oldest sustainable firewood traditions; many European hornbeam, hazel, and chestnut coppices have been continuously productive for centuries.

Wood smoke also carries real local air-quality costs (particulates, polycyclic aromatic hydrocarbons), and the public-health balance varies by stove technology and ventilation. Modern EPA-certified wood stoves burn dramatically cleaner than open hearths or old box stoves.

See also

Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.

• Enables: [[food-sovereignty]]
• Parallels: [[abundance]]
• Practices: [[agroforestry]]
• Produced by: [[alder]] · [[american-beech]] · [[apple]] · [[ash]] · [[bald-cypress]] · [[beech]] · [[birch]] · [[black-cherry]] · [[black-locust]] · [[cedar-of-lebanon]] · [[cherry]] · [[chestnut]] · [[eastern-hemlock]] · [[elm]] · [[fir]] · [[hickory]] · [[holly]] · [[hornbeam]] · [[juniper]] · [[larch]] · [[loblolly-pine]] · [[mulberry]] · [[oak]] · [[persimmon]] · [[pine]] · [[poplar]] · [[red-maple]] · [[shagbark-hickory]] · [[spruce]] · [[sugar-maple]] · [[sweet-gum]] · [[tamarack]] · [[tulip-tree]] · [[walnut]]

Sources

• Heating Value of Wood and Wood-Based Fuels, US Forest Service
• Wilson Forest Lands BTU rating tables (regional western and eastern hardwood/softwood)
• Virginia Tech forestry extension on cordwood properties
• Wikipedia — Firewood

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A concept entry in the 0mn1.one [[directory]].