Tree Allometrics

Larix laricina / Stem biomass

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

Stem biomassLarix laricina · PinaceaeCanadaRead from the original paper
Photo of Larix laricina
© Douglas Goldman · CC BY-SA · iNaturalist
Equation

As printed (Eq. 3)

y wood = β wood1D βwood2Hβwood3 + ewood

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

Stem biomass = 0.0276 * D^1.6724 * H^1.1443 + 0.012 * D^1.7059 * H^0.5811
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
y bark = β bark1D βbark2Hβbark3 + e bark
Equation · Eq. 3
Tamarack larch bwood1 0.0276
Equation · Table 4, Tamarack larch
bwood2 1.6724
Equation · Table 4, Tamarack larch
bwood3 1.1443
Equation · Table 4, Tamarack larch
bbark1 0.0120
Equation · Table 4, Tamarack larch
bbark2 1.7059
Equation · Table 4, Tamarack larch
bbark3 0.5811
Equation · Table 4, Tamarack larch
Tamarack larch 575 14.7±0.3 12.3±0.2 96.4±4.8
Trees measured · Table 2 (No. of trees)
(1.8;44.5) (2.2;30.5) (0.4;938.9)
Smallest DBH · Table 2, Tamarack larch (ranges of dbh, height, total biomass)
Stem 0.0070 0.92 26.9 3.80 0.0008 0.98 13.5 4.12
R² · Table 5, Tamarack larch (AdjRSq in the dbh- and height-based set, second block)
Trees measured
575
DBH range
1.8–44.5 cm
Height range
2.2–30.5 m
R²
0.98
Method
Nonlinear seemingly unrelated regression with weight functions; additivity constrained so compartments sum to total
Where
Canada: Alberta, Manitoba, Newfoundland and Labrador, Nova Scotia, Northwest Territories, Ontario, Quebec, Saskatchewan (ENFOR archival data, early 1980s)
Last checked
2026-11-03
Calculate
Height from
101
Stem biomass (kg)
47.6
Carbon (kg), ×0.47
175
CO₂e (kg), ×44/12
Fitted DBH range050100150200250300350510152025303540DBH (cm)Stem biomass (kg)Stem biomass

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%.

InputsExpectedWe getFrom
D = 20, H = 15101101Computed from the printed form
computed from the published form at dbh = 20 cm, H = 15 m

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