Tree Allometrics

Tsuga canadensis / Stem biomass

Canadian national equation, eastern hemlock, dbh and height (stem wood plus stem bark; Table 4)

Stem biomassTsuga canadensis · PinaceaeCanadaRead from the original paper

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Equation

As printed (Eq. 3)

y wood = β wood1D βwood2Hβwood3 + ewood

In this library's units, ready to compute (kg)

Stem biomass = 0.0257 * D^1.9277 * H^0.8576 + 0.0118 * D^1.9893 * H^0.47

D: Diameter at breast height (1.3 m), cm
H: Total tree height, m

Stem from ground level to tree top, stem wood plus stem bark; the stem is the sum of the two compartment equations. r2 is the adjusted R² (AdjRSq) of this compartment in Table 5. Fitted on the original scale (weighted nonlinear seemingly unrelated regression), so there is no back-transform correction. Dead branches, cones and fruits are not part of aboveground biomass in this work (Materials). Stand type was not always recorded. Ung, Bernier & Guo (2008) later revised parameters for some species with British Columbia data; not used here.

Source

Lambert, M.-C., Ung, C.-H., Raulier, F. (2005). Canadian national tree aboveground biomass equations. Canadian Journal of Forest Research, 35(8), 1996–2018.

doi:10.1139/x05-112 · Paywalled · copy we read

y bark = β bark1D βbark2Hβbark3 + e bark

Equation · Eq. 3

Eastern hemlock bwood1 0.0257

Equation · Table 4, Eastern hemlock

bwood2 1.9277

Equation · Table 4, Eastern hemlock

bwood3 0.8576

Equation · Table 4, Eastern hemlock

bbark1 0.0118

Equation · Table 4, Eastern hemlock

bbark2 1.9893

Equation · Table 4, Eastern hemlock

bbark3 0.4700

Equation · Table 4, Eastern hemlock

Eastern hemlock 235 24.1±0.9 14.4±0.4 286.9±20.5

Trees measured · Table 2 (No. of trees)

(1.3;51.4) (2.3;26.5) (0.6;1406.6)

Smallest DBH · Table 2, Eastern hemlock (ranges of dbh, height, total biomass)

Stem 0.0013 0.94 59.5 4.31 0.0074 0.97 45.0 3.52

R² · Table 5, Eastern hemlock (AdjRSq in the dbh- and height-based set, second block)

Trees measured: 235
DBH range: 1.3–51.4 cm
Height range: 2.3–26.5 m
R²: 0.97
Method: Nonlinear seemingly unrelated regression with weight functions; additivity constrained so compartments sum to total
Where: Ontario and Quebec, Canada (ENFOR archival data, early 1980s)
Last checked: 2026-11-03

Calculate

DBH (cm)Height (m)

Height from

101

Stem biomass (kg)

47.4

Carbon (kg), ×0.47

174

CO₂e (kg), ×44/12

Shaded: the DBH range the model was fitted on. Other inputs held at the values above.

Checks this equation passes

On every build, the library's form and the paper's own form (in its units) must both give these values within 1%.

Inputs	Expected	We get	From
D = 20, H = 15	101	101	Computed from the printed form computed from the published form at dbh = 20 cm, H = 15 m

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Related

Canadian national equation, eastern hemlock, dbh only (stem wood plus stem bark; Table 3) · Lambert et al. 2005 · DBH
Canadian national equation, alpine fir, dbh only (branches; Table 3) · same paper · Branch biomass
Canadian national equation, alpine fir, dbh and height (branches; Table 4) · same paper · Branch biomass
Canadian national equation, alpine fir, dbh and height (foliage; Table 4) · same paper · Foliage biomass
Canadian national equation, alpine fir, dbh and height (stem wood plus stem bark; Table 4) · same paper · Stem biomass
Canadian national equation, alpine fir, dbh and height (sum of wood, bark, branches, foliage; Table 4) · same paper · Aboveground biomass
Canadian national equation, alpine fir, dbh only (foliage; Table 3) · same paper · Foliage biomass
Canadian national equation, alpine fir, dbh only (stem wood plus stem bark; Table 3) · same paper · Stem biomass
Canadian national equation, alpine fir, dbh only (sum of wood, bark, branches, foliage; Table 3) · same paper · Aboveground biomass

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