Tree Allometrics

Tectona grandis / Stem volume

Teak stem volume from D (V1, local)

Stem volumeTectona grandis · LamiaceaeNepalplantationRead from the original paper
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Equation

As printed (Table 6 (form V1), Table 7 (estimates))

V = a + b × (dbh) ... a -0.4720, b 0.0414

In this library's units, ready to compute (m³)

Stem volume = -0.4720 + 0.0414 * D
D
Diameter at breast height (1.3 m), cm

Volume is the total stem volume above the 0.10 m stump (stump excluded), summed from log sections and the tree top. Paper calls V1 the local volume equation. R2 0.949 (adj. 0.944), RMSE 0.20 m3 (Table 7). Predicts negative volume for small trees.

Source
31 (70 % of the data) were randomly selected to build the model
Trees measured · Section 2.2
Trees measured
31
DBH range
6.37–58.92 cm
Height range
5.7–26.1 m
R²
0.949
Method
least squares on training set (31 of 44 felled trees)
Where
Sagarnath Forestry Development Project, Sarlahi district, central lowland Nepal
Last checked
2026-11-02
Calculate
0.356
Stem volume (m³)
Fitted DBH range00.20.40.60.811.2510152025303540DBH (cm)Stem volume (m³)Stem volume

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 = 200.3560.356Computed from the printed form
computed from the published form (coefficients as printed); not meaningful below about 11.4 cm (negative volume)
D = 350.9770.977Computed from the printed form
computed from the published form (coefficients as printed); not meaningful below about 11.4 cm (negative volume)
D = 551.811.81Computed from the printed form
computed from the published form (coefficients as printed); not meaningful below about 11.4 cm (negative volume)

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