Spalted Birch (possibly Paper or Yellow Birch)
Betula papyrifera or Betula alleghaniensis • Hardwood
Grain Pattern
Straight to slightly irregular end-grain showing distinct spalted patterns. Spalting consists of black zone lines caused by fungal activity, creating irregular, map-like markings across the transverse surface.
Color Description
Creamy white to light tan sapwood with a darkened, brownish pith center. The surface shows significant silvery-gray oxidation and spalting marks. Birch typically darkens to a yellow-gold with age and light exposure.
Hardness Rating
995 lbf to 1,260 lbf (Medium to Hard)
Durability Rating
Non-durable; highly susceptible to rot and decay, which is the process that allows the 'spalting' fungus to colonize the wood.
Common Uses
Woodturning (bowls, platters), decorative veneers, small crafts, spoons, and firewood. Not suitable for structural use due to fungal degradation.
Geographic Origin
Northern North America (United States and Canada) and Northern Europe.
Market Value & Sustainability
Estimated Market Value
$5.00 - $12.00 per board foot depending on the intensity of the spalted figure.
Wood Age Estimate
Freshly cut branch or small trunk (approx. 5-10 years old based on ring count) but shows signs of being deadwood or 'downed' for 1-2 years to allow for fungal spalting.
Sustainability Status
Least Concern (IUCN); widely available and not CITES listed. Birch is generally considered a sustainable hardwood.
Workability
Easy to work with both hand and machine tools, though the spalted (decayed) areas may be softer or 'punky,' requiring sharp tools to avoid tearout. Glues and finishes well.
Notable Features
Features distinct black zone lines (spalting). Birch has no characteristic odor. The fine, uniform texture makes it excellent for turning.
Finish Recommendations
Clear penetrating oils (tung or linseed) or polyurethane to stabilize the wood and highlight the black fungal lines. A sanding sealer is recommended for punky areas.
Identification Confidence
Medium-High; the bark texture, diffuse-porous end grain, and characteristic black zone-line spalting are classic indicators of the Betula genus.