Tree Allometrics

Populus grandidentata / Stem biomass

Canadian national equation, largetooth aspen, dbh only (stem wood plus stem bark; Table 3)

Stem biomassPopulus grandidentata · SalicaceaeCanadaRead from the original paper
No openly licensed photo yet
Equation

As printed (Eq. 2)

y wood = β wood1D βwood2 + ewood

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

Stem biomass = 0.0959 * D^2.343 + 0.0308 * D^2.224
D
Diameter at breast height (1.3 m), cm

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 βbark2 + e bark
Equation · Eq. 2
Largetooth aspen bwood1 0.0959
Equation · Table 3, Largetooth aspen
bwood2 2.3430
Equation · Table 3, Largetooth aspen
bbark1 0.0308
Equation · Table 3, Largetooth aspen
bbark2 2.2240
Equation · Table 3, Largetooth aspen
Largetooth aspen 100 15.8±0.7 16.9±0.6 114.8±12.2
Trees measured · Table 2 (No. of trees)
(1.5;39.2) (2.3;28.9) (1.0;641.2)
Smallest DBH · Table 2, Largetooth aspen (ranges of dbh, height, total biomass)
Stem 0.4481 0.94 25.7 2.29 0.0011 0.98 14.7 3.94
R² · Table 5, Largetooth aspen (AdjRSq in the dbh-based set, first block)
Trees measured
100
DBH range
1.5–39.2 cm
R²
0.94
Method
Nonlinear seemingly unrelated regression with weight functions; additivity constrained so compartments sum to total
Where
Ontario, Canada (ENFOR archival data, early 1980s)
Last checked
2026-11-03
Calculate
131
Stem biomass (kg)
61.7
Carbon (kg), ×0.47
226
CO₂e (kg), ×44/12
Fitted DBH range0100200300400500600700510152025303540DBH (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 = 20131131Computed from the printed form
computed from the published form at dbh = 20 cm

Report a problem with this equation · JSON

Related

Compare these curves