# Teak stem volume from D and H (V5, generic)

Stem volume equation for Tectona grandis, Nepal, from Koirala et al. 2017. 31 trees, DBH 6.37–58.92 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Koirala et al. 2017 (Abstract; Table 7, model V5):

> V = [0.3364 + (0.0685 × dbh) + (−0.097 × H)]

Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#equation

In this library's units, ready to compute (stem volume in m³):

```
Stem volume = 0.3364 + 0.0685 * D - 0.0970 * H
```

Inputs: D = Diameter at breast height (1.3 m) (cm); H = Total tree height (m).
The source's own form: 0.3364 + 0.0685 * dbh - 0.0970 * H, with dbh in cm, H in m; output in m3.
Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#canonical

## What it covers

- Output: Stem volume, m³
- Taxon: Tectona grandis (species), family Lamiaceae; broadleaf
- Where: Sagarnath Forestry Development Project, Sarlahi district, central lowland Nepal. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#where
- Biomes: tropical
- Stand: plantation
- Trees measured: 31. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#n_trees
- DBH range: 6.37–58.92 cm. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#dbh
- Height range: 5.7–26.1 m. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#height
- R²: 0.988. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#r2
- Method: least squares on training set (31 of 44 felled trees). Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#checked_at

A missing fit statistic is one the source doesn't state, or that we haven't recorded; it is never estimated. Outside the stated DBH range or region, the equation is an extrapolation.

## Source

Koirala, A., Kizha, A. R., & Baral, S. (2017). Modeling height-diameter relationship and volume of teak (Tectona grandis L.f.) in central lowlands of Nepal. Journal of Tropical Forestry and Environment, 7(1), 28–42.

- DOI: https://doi.org/10.31357/jtfe.v7i1.3020
- Access: open access
- Copy we read: https://web.archive.org/web/2024/http://journals.sjp.ac.lk/index.php/JTFE/article/download/3020/2093
- Every equation from this source: https://treeallometry.org/sources/koirala-2017/
- Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#source

## The facts, in the source's words

**Equation** (Abstract; Table 7, model V5):

> V = [0.3364 + (0.0685 × dbh) + (−0.097 × H)]

Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#equation

**Trees measured** (Section 2.2):

> 31 (70 % of the data) were randomly selected to build the model

Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#quote-fit-n-trees

**Our note:** In the paper H is the height predicted from the H2 equation (H*), not the measured height; with measured height the fit is not what the authors validated. Stump excluded from volume. R2 0.988 (adj. 0.985), RMSE 0.09 m3 (Table 7). The only candidate with all parameters significant.

## Checks this equation passes

On every build, the library's form and the source's own form (in its units) must both give these values within 1%.

| Inputs | Expected | We get | From |
| --- | --- | --- | --- |
| D = 20, H = 12 | 0.542 | 0.542 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 35, H = 19 | 0.891 | 0.891 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 55, H = 24 | 1.78 | 1.78 | Computed from the printed form: computed from the published form (coefficients as printed) |

Cite: https://treeallometry.org/equations/koirala-2017-v-dbh-h/#checks

## How to cite

Cite the source for the equation: Koirala, A., Kizha, A. R., & Baral, S. (2017). Modeling height-diameter relationship and volume of teak (Tectona grandis L.f.) in central lowlands of Nepal. Journal of Tropical Forestry and Environment, 7(1), 28–42. https://doi.org/10.31357/jtfe.v7i1.3020

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Teak stem volume from D and H (V5, generic)", checked 2026-11-02, https://treeallometry.org/equations/koirala-2017-v-dbh-h/. Data CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Quotes are the authors' words.

Data for this equation: https://treeallometry.org/data/equations/koirala-2017-v-dbh-h.json
Report a problem: email info@restorationscope.com with the equation id (koirala-2017-v-dbh-h) and where the right value appears.