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πŸͺ΅ Firewood: Cutting, Splitting, Seasoning & Burning

How to keep a household warm and cooking with wood: which local trees give the most heat, how much you'll need, felling and bucking safely, splitting, drying wood in our wet winters, burning it cleanly, keeping the chimney from catching fire, handling ashes in fire country, and growing your own firewood from oak, madrone and tanoak stumps. The manuals are in Firewood\ (Cutting-Felling, Splitting-Seasoning, Burning-Stoves-Chimneys, Woodlot); saws, axes and sharpening are in Engines-Motors\Chainsaws-and-Saws and the Blacksmithing guide.

⚠️ Rules that prevent the worst injuries and fires


πŸ”₯ Which wood, and how much

All dry wood gives about the same heat per pound (~9,000 BTU) β€” so heavier (denser) wood gives more heat per cord (PNW-GTR-810, p. 9).

Local tree Heat per cord (million BTU, dry) How it burns
Oregon white oak ~30 Hard to light, long-lasting coals β€” best overnight wood
Pacific madrone ~30 Same; dries slowly and checks
Tanoak ~24–27 (estimated from density) Excellent coals
California black oak ~22–24 (estimated) Good coals
Douglas-fir ~21–24 Easy to light, hot, some sparks
Bigleaf maple ~20–24 (estimated) Good all-round
Red alder ~17–18 Fast, clean; spring and fall fires
Ponderosa pine / sugar pine ~15–22 Lights easily, burns fast, poor coals
Incense cedar ~15–17 (estimated) Kindling β€” lights instantly, sparks a lot

(Oak, madrone, fir, alder and pine from OSU EC1628, p. 4 and PNW-GTR-810; burn traits from U. of Minnesota, p. 14.)

Use the right wood for the job: cedar and pine for kindling and quick spring or fall fires; oak, madrone and tanoak for cold nights and overnight burns (rule of thumb). Creosote comes mostly from wet wood and smoldering fires, more than from the kind of tree (E-1388, p. 2).

How much:

Two woodpiles: a full cord, 4 ft high, 8 ft long and 4 ft deep, and a face cord with the same 4-by-8-ft face but only 16 in deep A full cord and a face cord: three face cords of 16-in wood make one cord (a diagram drawn for this guide).

πŸ“š Go deeper: PNW-GTR-810 Fuelwood Characteristics β€” tables for every Northwest tree; CMHC Guide to Residential Wood Heating; OSU EC1628. Pictures: Firewood, Pacific madrone, Oregon white oak.

🌲 Felling trees safely

(OSU EC 1124 Safe and Effective Use of Chain Saws, written for Oregon woodland owners; USFS sawyer course)

  1. Size it up. Don't fell in gusty wind, fog, snow or ice. Check the lean from two sides (a weight on a string works), look up for dead limbs ("widow-makers") and vines tying it to other trees, and bore in once to check for rot (drawing). Alder and maple often have rotten hearts (EC 1124, pp. 3–4).
  2. Dead trees and snags are a different job. They can fail across a circle 1–1Β½ times their height, farther downhill (USFS FS-1273, p. 36). Tanoak killed by Sudden Oak Death rots fast and can snap before it's fully dead β€” treat it as very high risk, and don't move infected tanoak wood to new areas (FS-1273, p. 181).
  3. Clear an escape path about 45Β° back and away from the fall direction, and clear brush around the trunk (EC 1124, p. 5).
  4. Notch (undercut) on the side it will fall, about one-third of the way through the trunk. The two cuts must meet exactly β€” if they don't, the trunk can split up and kick back ("barber chair"). An open-face notch (about 90Β°) is the most controlled (EC 1124, pp. 6–7; the three notches).
  5. Back cut from the other side, level and about 1 inch higher than the floor of the notch. Stop to leave a hinge of uncut wood 1–1Β½ in thick β€” the hinge steers the tree. Wedge the back cut early. When it goes, set the saw down and walk out your escape path (EC 1124, pp. 7–8; back cut and hinge).
  6. Hung up in another tree? Don't cut the tree it's leaning on and don't work under it β€” see the professional fallers' methods for hang-ups and leaners (WorkSafeBC Part 2).

Two drawings of a dead tree's fall zone: on flat ground a circle 1 to 1.5 times the tree's height all around; on a slope the zone stretches farther downhill where the tree can slide or roll A dead tree can land anywhere within 1 to 1Β½ times its height, and farther downhill (FS-1273, p. 36).

A tree seen from above with the direction of fall marked, and an escape path and an alternate path each running back at 45Β° from the opposite side to a safety zone Clear two escape paths at 45Β° back and away from the line of fall (An Ax to Grind, p. 47).

Side view of a trunk being felled: an open-face notch one-third through on the side it will fall, a level back cut from the other side about 1 inch above the notch floor, a strip of uncut hinge wood 1 to 1Β½ inches thick between them, and a wedge driven into the back cut The notch, back cut, hinge and wedge in steps 4 and 5 (a diagram drawn for this guide).

With hand tools: a sharp crosscut saw and axe still fell and buck trees when fuel runs out β€” the USFS Crosscut Saw Manual, Saws That Sing (how the teeth cut) and An Ax to Grind (felling with an axe) cover it, and the Engines guide covers chainsaw care.

πŸ“š Go deeper: OSU EC 1124 β€” the whole felling sequence with drawings; WorkSafeBC Faller Standard Part 1; USFS hazard-tree guide β€” reading snags and rot. Pictures: how far a snag can reach, FS-1273 p. 36, felling factors, U. of Minnesota p. 9, Tree felling.

πŸͺš Bucking and limbing

Two logs seen from the side. One held up at both ends sags in the middle: cut 1 is a shallow cut down from the top, cut 2 comes up from below to meet it. One held up at one end droops at the free end: cut 1 is a shallow cut up from below, cut 2 comes down from the top Cut the squeezed side first so the saw isn't pinched (a diagram drawn for this guide).

πŸ“š Go deeper: WorkSafeBC Part 2 β€” binds and safe bucking; U. of Minnesota β€” bucking without pinching, p. 11. Pictures: chainsaw kickback, EC 1124 p. 11, limbing with an axe, An Ax to Grind p. 48, bucking with an axe, p. 50, Chainsaw.

πŸͺ“ Splitting

(UW-Extension Harvesting Firewood, pp. 15–16; U. of Minnesota, pp. 11–12)

Drawings of splitting wood with an axe: rounds and halves set up to split safely, a foot in the way of the axe marked NEVER, an axe striking a steel wedge marked NEVER, and a chopping block for kindling Safe and unsafe ways to split: never with your foot in the swing, and never strike steel with an axe (An Ax to Grind, p. 51).

πŸ“š Go deeper: UW-Extension Harvesting Firewood from Your Woods; An Ax to Grind β€” axes and mauls. Pictures: twist the axe as it bites, An Ax to Grind p. 52, Axe, Wedge.

β˜€οΈ Seasoning: drying wood in a wet climate

Wet wood wastes heat β€” a ton of wood at 60% moisture gives about 5.6 million BTU; dried to 20% it gives about 10.7 million (U. of Minnesota, p. 14). It also makes creosote and smoke.

πŸ“š Go deeper: EPA Wet Wood is a Waste; UW-Extension β€” stacking and drying; CMHC β€” drying tests, p. 61. Pictures: Wood drying.

🏠 Burning safely: stoves, chimneys, ashes

Burn hot and dry. Smoldering fires and wet wood coat the chimney with creosote, which condenses below about 250 Β°F and turns to sticky tar below 150 Β°F (E-1388, p. 2). Flaky, dry creosote means you're burning well; black, shiny tar means you're not (CMHC, p. 46).

Chimney cleaning: at least once a year; some say every 3 cords. After cleaning, check after 2 weeks, 1 month and 2 months to learn how fast yours builds up, and check the stovepipe every 2–3 months (E-1388, pp. 3, 5). A stiff brush on rods or a rope (chimney brushes), from the top down, with the stove sealed below (rule of thumb).

Chimney fire β€” roaring sound, shaking pipes, sparks out the top (E-1388, p. 3):

  1. Close every air inlet and the damper to starve it.
  2. Get everyone out; have someone watch the roof for sparks and check the attic.
  3. A dry-chemical (ABC) extinguisher or baking soda thrown into the firebox can knock it down.
  4. Chimney fires reach 2,000–3,000 Β°F β€” inspect the chimney before using it again; metal chimneys can be ruined after 2–3 fires.

Clearances: follow the stove's label. For an unlabeled stove: 36–48 in from anything that burns, 18 in for stovepipe, and a non-combustible floor pad reaching 18 in in front (CMHC, p. 31; U. of Minnesota, p. 24; clearances and a wall shield). Keep wood, furniture and drying clothes 3 ft away (USFA card).

A wood stove seen from above in the corner of a room: 36–48 in from each wall that can burn, the stovepipe circled by an 18-in clearance, a fireproof floor pad reaching 18 in in front, and the woodbox 3 ft away Clearances for a stove with no label, seen from above (a diagram drawn for this guide).

Ashes in fire country (Crystal Lakes fire district; USFA):

Carbon monoxide: smoke and CO alarms near bedrooms; both wear out after about 10 years (Crystal Lakes, p. 2).

πŸ“š Go deeper: E-1388 The Creosote Problem; CMHC β€” stoves, chimneys and clearances; Aprovecho Capturing Heat β€” homemade stoves; Arkansas Basics of Heating with Firewood. Pictures: chimney height above the roof, U. of Minnesota p. 25, Wood-burning stove, Chimney sweep.

🌳 Growing your own: thinning and coppicing

Our hardwoods regrow from the stump β€” cut once, harvest again and again ("coppicing") (USFS PSW-GTR-185):

Thin for firewood and fire safety at the same time: remove small, crowded trees and lower limbs ("ladder fuels", drawing) and space out the crowns β€” the cut becomes firewood, and the woods burn less hot in a wildfire (OSU EC 1573, p. 3; EC 1574). In oak woodland, removing the Douglas-fir crowding the oaks gives both firewood and healthier oaks (KBO/Lomakatsi oak guide).

πŸ“š Go deeper: PSW-GTR-185 β€” sprouting of black oak, tanoak and madrone; OSU EC 1573 β€” thinning; Restoring Oak Habitats in Southern Oregon; Wikipedia: coppicing. Pictures: a stand before and after thinning, EC 1573 p. 3, California black oak.

πŸ“† A firewood year (rule of thumb)

When Do this
Jan–Mar Fell and coppice hardwoods (best resprouting, sap down, easy to see the woods). Buck to length.
Mar–May Split and stack everything for next winter, in sun and wind. Clean the chimney after the heating season.
June–Sept Fire season: little or no saw work; let the woodpile dry. Clear brush around the house and woodpile.
Oct Cover the tops of the stacks before the rains; move a month's wood into the shed or porch. Check the stovepipe.
Nov–Feb Burn last year's wood; check the chimney after the first month. Haul ashes to the metal can.

πŸ“š Go deeper: UW-Extension Harvesting Firewood from Your Woods β€” from standing tree to woodpile; USFS 1943 summer-seasoning test β€” why early cutting matters; Firewood.

πŸ–ΌοΈ Pictures & diagrams

Look before you try it. πŸ–ΌοΈ = drawings in the books on this drive; πŸ“· = photos in the offline Wikipedia.

Felling

Bucking, limbing and saws

Splitting, stacking and storing

Stoves, chimneys and ashes

Growing firewood


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