Tree Allometrics

Thuja occidentalis / Stem biomass

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

Stem biomassThuja occidentalis · CupressaceaeCanadaRead 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 = 0.0295 * D^1.7026 * H^0.9428 + 0.0076 * D^1.7861 * H^0.6132

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 white-cedar bwood1 0.0295

Equation · Table 4, Eastern white-cedar

bwood2 1.7026

Equation · Table 4, Eastern white-cedar

bwood3 0.9428

Equation · Table 4, Eastern white-cedar

bbark1 0.0076

Equation · Table 4, Eastern white-cedar

bbark2 1.7861

Equation · Table 4, Eastern white-cedar

bbark3 0.6132

Equation · Table 4, Eastern white-cedar

Eastern white-cedar 184 20.8±0.9 11.8±0.3 117.2±9.3

Trees measured · Table 2 (No. of trees)

(2.1;66.2) (1.9;21.9) (1.0;917.4)

Smallest DBH · Table 2, Eastern white-cedar (ranges of dbh, height, total biomass)

Stem 0.0172 0.95 22.5 2.99 0.0013 0.97 16.7 3.62

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

Trees measured: 184
DBH range: 2.1–66.2 cm
Height range: 1.9–21.9 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

70.6

Stem biomass (kg)

33.2

Carbon (kg), ×0.47

122

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	70.6	70.6	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 white-cedar, 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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