General woodworking advice describes average material. Five species common to British Columbia's Interior each show where that advice needs checking against the board on hand: in white oak, grain orientation is a structural decision; yellow cedar is not a true cedar; western larch needs its resin pockets sealed; "maple" may be bigleaf maple, not hard maple; and Douglas-fir varies by grade and grain orientation [1][3][4][5][6][7].
White oak: orientation is a structural decision
White oak shrinks about 10.5% tangentially and about 5.6% radially from green to oven-dry, a tangential-to-radial ratio of about 1.9 [1].
The Wood Handbook's dimensional change coefficients for white oak are 0.00376 tangential and 0.00194 radial per 1% change in moisture content, so a quartersawn white oak panel moves about half as much across its width as a flat-sawn panel [2].
Worked example: a 24-inch flat-sawn white oak top through a 4% moisture content swing moves 24 × 0.00376 × 4 = about 0.36 inch across its width. The same top quartersawn moves 24 × 0.00194 × 4 = about 0.19 inch [2].
A wide flat-sawn white oak top needs a movement plan: a calculated movement figure and joinery that lets the top move [2].
In quartersawn white oak, the ray fleck and the lower movement come from the same cut. Choose the cut when buying the lumber, not at the bench [2][3].
Yellow cedar: the name is not the species
Yellow cedar is not a true cedar. It belongs to the cypress family, Cupressaceae, and is also sold as Alaska yellow cedar, yellow cypress and Nootka cypress [4].
Yellow cedar is heavier than western red cedar and has a finer, more uniform texture [4].
Extractives at the surface of yellow cedar can interfere with oil-based finishes. A finish problem on yellow cedar may come from the wood's chemistry rather than the application technique [5].
Western larch: know the species' failure mode
Western larch can contain resin pockets. Spot-coat each resin pocket with dewaxed shellac before finishing [6].
Bigleaf maple: confirm which maple
Bigleaf maple and hard maple are different species with different movement coefficients. The Wood Handbook lists bigleaf maple at 0.00248 tangential and hard maple at 0.00353 tangential per 1% change in moisture content [2].
A plan written for hard maple does not carry correct movement figures for bigleaf maple. Ask the supplier which maple is on the rack [2][7].
Figured bigleaf maple is best bought in person, because its figure varies from board to board [8].
Douglas-fir: grade and grain change the material
Construction-grade Douglas-fir and furniture-grade vertical-grain Douglas-fir behave like different materials, although they are the same species [9].
Grade, grain orientation and moisture content decide whether a Douglas-fir board suits furniture. Clear, vertical-grain, kiln-dried Douglas-fir is the furniture grade [9][10].
Coast-type Douglas-fir shrinks about 7.6% tangentially and about 4.8% radially, so a vertical-grain board moves less across its width than a flat-sawn board [10].
The common lesson
In each of the five species, the deciding facts are specific: the species' true identity, the cut, the grade, the moisture content and the climate the piece will live in. Check general advice against those facts before building.
Sources
- USDA Forest Products Laboratory, Wood Handbook: Wood as an Engineering Material (FPL-GTR-190), Chapter 4, Table 4-3 (Shrinkage Values).
- USDA Forest Products Laboratory, Wood Handbook (FPL-GTR-282), Chapter 13, Equation 13-3 and Table 13-5, dimensional change coefficients, valid 6 to 14% moisture content (as listed in Hewn's notes, entries HEU-R735 and HEU-R739).
- Hewn heuristic data, Reed entry HEU-R954 (white oak ray fleck), 2026-03-16, sourced in the entry to the US Forest Service Wood Handbook, unreviewed.
- Callitropsis nootkatensis (Wikipedia), US Fish & Wildlife "Yellow Cedar", conifers.org "Cupressus nootkatensis", JW Lumber factsheet (Forintek Canada Corp.), against Hewn heuristic entry HEU-R956 (as listed in Hewn's notes, R956).
- JW Lumber factsheet (Forintek Canada Corp.) and USDA FPL tech sheet for yellow cedar, against Hewn heuristic entry HEU-R958, which the log marks only directionally confirmed (as listed in Hewn's notes, R958).
- Hewn heuristic entry HEU-R966, western larch finishing, Hewn internal, unreviewed; the resin pocket protocol was checked against wood-database.com "Western Larch" (as listed in Hewn's notes, Scout Block 93, R966).
- Hewn heuristic entry HEU-R968, bigleaf maple versus hard maple, checked against USDA FPL-GTR-190, OWIC and the Wood Database (as listed in Hewn's notes, R968).
- wood-database.com "Quilted Maple" and "Bigleaf Maple", and coastal BC dealer listings, against Hewn heuristic entry HEU-R969 (as listed in Hewn's notes, R969).
- NLGA Standard Grading Rules, woodcraft.com "Vertical Grain Douglas-Fir" and sawmillcreek.org, against Hewn heuristic entry HEU-R973 (as listed in Hewn's notes, R973).
- USDA Forest Products Laboratory, Wood Handbook: Wood as an Engineering Material (FPL-GTR-190), Chapter 4, Table 4-3a, coast-type Douglas-fir (as listed in Hewn's notes, entries R011 and R324).