# Gliricidia sepium height from D (non-rectangular hyperbola, Table 3)

Height equation for Gliricidia sepium, Indonesia, from Tiralla et al. 2013. 28 trees, DBH 7–44.1 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Tiralla et al. 2013 (Table 3):

> y = 0.5 x (a x x + b - sqrt((a x x + c)^2 - 4 x a x x x b)); H on DBH: a 1.0901, b 10.941, c 11.0, r 0.722

Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#equation

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

```
Height = 0.5 * (1.0901 * D + 10.941 - sqrt((1.0901 * D + 11.0)^2 - 4 * 1.0901 * D * 10.941))
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: 0.5 * (1.0901 * DBH + 10.941 - sqrt((1.0901 * DBH + 11.0)^2 - 4 * 1.0901 * DBH * 10.941)), with DBH in cm; output in m.
Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#canonical

## What it covers

- Output: Height, m
- Taxon: Gliricidia sepium (species), family Fabaceae; broadleaf
- Where: Bulili, Kecamatan Palolo, Central Sulawesi (shade trees in cacao agroforestry). Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#where
- Biomes: tropical
- Stand: agroforestry
- Trees measured: 28. Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#n_trees
- DBH range: 7–44.1 cm. Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#dbh
- Height range: 7.3–12.9 m. Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#height
- Method: non-rectangular hyperbola (Thornley 1976), maximum height fixed at 11 m. Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#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

Tiralla, N., Panferov, O., & Knohl, A. (2013). Allometric relationships of frequently used shade tree species in cacao agroforestry systems in Sulawesi, Indonesia. Agroforestry Systems, 87, 857-870.

- DOI: https://doi.org/10.1007/s10457-013-9602-4
- Access: open access
- Copy we read: https://link.springer.com/article/10.1007/s10457-013-9602-4
- Every equation from this source: https://treeallometry.org/sources/tiralla-2013/
- Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#source

## The facts, in the source's words

**Equation** (Table 3):

> y = 0.5 x (a x x + b - sqrt((a x x + c)^2 - 4 x a x x x b)); H on DBH: a 1.0901, b 10.941, c 11.0, r 0.722

Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#equation

**Trees measured** (Field measurements):

> 28 G. sepium trees

Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#quote-fit-n-trees

**Our note:** Formula typeset exactly as in the Table 3 caption. Authors state the best fit was obtained with maximum height fixed at 11 m (c = 11.0). Only a multiple correlation coefficient (r = 0.722) is given, not R2, so none is recorded.

## 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 = 10 | 10.1 | 10.1 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 30 | 10.9 | 10.9 | Computed from the printed form: computed from the published form (coefficients as printed) |

Cite: https://treeallometry.org/equations/tiralla-2013-h-gliricidia/#checks

## How to cite

Cite the source for the equation: Tiralla, N., Panferov, O., & Knohl, A. (2013). Allometric relationships of frequently used shade tree species in cacao agroforestry systems in Sulawesi, Indonesia. Agroforestry Systems, 87, 857-870. https://doi.org/10.1007/s10457-013-9602-4

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Gliricidia sepium height from D (non-rectangular hyperbola, Table 3)", checked 2026-11-02, https://treeallometry.org/equations/tiralla-2013-h-gliricidia/. 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/tiralla-2013-h-gliricidia.json
Report a problem: email info@restorationscope.com with the equation id (tiralla-2013-h-gliricidia) and where the right value appears.