Eastern hemlock
Tsuga canadensis
Eastern hemlock measures 500 lbf on the Janka scale, about 39% as hard as northern red oak.
- Of the three hemlocks in the handbook, none is softer or lighter, and none bends more easily, shrinks less across the face or has a higher T/R ratio.
- California red fir has exactly the same Janka figure.
- Across all 155 woods it falls in the top fifth for T/R ratio and in the bottom fifth for hardness, density, bending strength, stiffness, radial shrinkage and volumetric shrinkage.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
Eastern hemlockU.S. softwoods medianOther woods
Cupping tendency
2.2715th highest of 1551.092.90Stiffness
1.20 M psi8.3 GPa19th most flexible of 1550.54 M psi4.06 M psiBending strength
8,900 psi61.4 MPa22nd weakest of 1554,300 psi29,900 psiDensity
0.380.40 at 12% MC28th lightest of 1550.250.96Janka hardness
500 lbf2,224 N30th softest of 15518th of 37 U.S. softwoods240 lbf3,680 lbfShrinkage across the face
6.8%radial 3.0%40th lowest of 1553.5%12.7%
How much it moves
Most of its movement runs along the rings (T/R 2.27): quartersawn, the same board would lose 0.18 in. instead of 0.41 in.
0.41 in.
off a 6-inch flatsawn board, green to oven-dry
- Tangential
- 6.8%
- Radial
- 3.0%
- Volume
- 9.7%
- T/R ratio
- 2.27 (141st most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- White fir
4% softer · 3% lighter · shrinks 0.2 points more across the face
- Jack pine
14% harder · 5% heavier · shrinks 0.2 points less across the face
- Balsam fir
24% softer · 13% lighter · shrinks 0.1 points more across the face
Among the hemlocks
3rd hardest of 3, lbf.
Laboratory values
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Work to maximum load | 6.70in-lbf/in³ | 6.80in-lbf/in³ | +1% | 46.9kJ/m³ |
| Modulus of elasticity | 1.07M psi | 1.20M psi | +12% | 8.27GPa |
| Modulus of rupture | 6,400psi | 8,900psi | +39% | 61.4MPa |
| Shear parallel to grain | 850psi | 1,060psi | +25% | 7.30MPa |
| Side hardness | 400lbf | 500lbf | +25% | 2,224N |
| Impact bending | 21in. | 21in. | ±0% | 533mm |
| Compression parallel to grain | 3,080psi | 5,410psi | +76% | 37.3MPa |
| Compression perpendicular | 360psi | 650psi | +81% | 4.50MPa |
| Tension perpendicular | 230psi | not tested | — | — |
Wood Handbook Table 5-3b, Table 4-3. Data & method · Guides