Tree Allometrics

Equations / Aboveground biomass

Oneseed juniper AGB from equivalent stem diameter (dry field measurement)

Aboveground biomassJuniperus monosperma · CupressaceaeUnited StatesnaturalRead from the original paper
Photo of Juniperus monosperma
© Paul Asman and Jill Lenoble · CC BY · iNaturalist
Equation

As printed (Table 2)

ESDDry (cm) Y = a * Xb 0.005 (0.007) 3.038 (0.352) 38.55 15

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

Aboveground biomass = 0.005 * DRC^3.038
DRC
Root collar / stem base diameter, cm

The predictor is ESD, the equivalent root-collar diameter: square root of the sum of squared root-collar diameters (DRC) of all stems of the individual, bark included. Mapped to canonical DRC (equal to the DRC for a single-stem tree). AGB includes wood and leaf and twig tissue, in kg dry mass. The coefficient a is printed to only three decimals, so predictions for small trees are coarse. Range fields hold the ESD range, not DBH.

Source
ESDDry 3.3 47.2
DBH range · Table 1 (min, max, N=15)
Trees measured
15
DBH range
3.3–47.2 cm
Method
power model, nonlinear least squares (Gauss-Newton)
Where
central New Mexico (34.429N, 105.861W)
Last checked
2026-11-02
Calculate
5.457
Aboveground biomass (kg)
2.565
Carbon (kg), ×0.47
9.405
CO₂e (kg), ×44/12
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
DRC = 105.465.46Computed from the printed form
hand-computed from the published form
DRC = 2044.844.8Computed from the printed form
hand-computed from the published form
DRC = 40368.2368.2Computed from the printed form
hand-computed from the published form

Report a problem with this equation · JSON

Related

Compare these curves