Tree Allometrics

Pinus roxburghii / Height

Chir pine height from D, quadratic (M2)

HeightPinus roxburghii · PinaceaeNepalnaturalRead from the original paper
Photo of Pinus roxburghii
© Hildegard Klein · CC BY · iNaturalist
Equation

As printed (Table 4, M2)

height=1.1052804+0.6252304*dbh−0.0021242*dbh2

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

Height = 1.1052804 + 0.6252304 * D - 0.0021242 * D^2
D
Diameter at breast height (1.3 m), cm

r2 is the adjusted R2 as printed in Table 6 (RMSE 3.639). Fitted on the 80% training split of the FRA 2018 sample; the paper's n is ambiguous (610 'sample plots' vs 610 trees in Table 3), so n_trees and ranges are left out. Table 6 coefficient columns differ from Table 4; Table 4 (printed formulas, consistent with Table 3 class means) is used.

Source
R²
0.72
Method
polynomial (degree 2) regression
Where
Nepal, Forest Resource Assessment 2018 plots
Last checked
2026-11-02
Calculate
7.15
Height (m)
0510152025510152025303540DBH (cm)Height (m)Height

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 = 107.157.15Computed from the printed form
computed from the published form (coefficients as printed)
D = 2515.415.4Computed from the printed form
computed from the published form (coefficients as printed)
D = 5027.127.1Computed from the printed form
computed from the published form (coefficients as printed)

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