# Lodgepole pine branch biomass, simple SUR (D only)

Branch biomass equation for Pinus contorta, United States, from Poudel & Temesgen 2016. 33 trees, DBH 13.5–42.9 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Poudel & Temesgen 2016 (Eqs. 2-5 (X1 = ln DBH) and Table 3, Simple SUR, Lodgepole pine):

> Branch = exp(a31 + a32*X1); a31 = -3.384, a32 = 2.202

Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#equation

In this library's units, ready to compute (branch biomass in kg):

```
Branch biomass = exp(-3.384 + 2.202 * ln(D))
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: exp(-3.384 + 2.202 * ln(D)), with D in cm; output in kg.
Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#canonical

## What it covers

- Output: Branch biomass, kg
- Taxon: Pinus contorta (species), family Pinaceae; conifer
- Where: Oregon, USA (several forests). Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#where
- Biomes: temperate
- Stand: mixed
- Trees measured: 33. Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#n_trees
- DBH range: 13.5–42.9 cm. Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#dbh
- Method: seemingly unrelated regression (simple SUR), component equations constrained to sum to total, fitted in original scale. Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#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

Poudel, K. P., & Temesgen, H. (2016). Methods for estimating aboveground biomass and its components for Douglas-fir and lodgepole pine trees. Canadian Journal of Forest Research, 46(1), 77-87.

- DOI: https://doi.org/10.1139/cjfr-2015-0256
- Access: open access
- Copy we read: https://utoronto.scholaris.ca/bitstreams/36d392bb-40cc-4598-b73c-6745768b0acf/download
- Every equation from this source: https://treeallometry.org/sources/poudel-2016/
- Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#source

## The facts, in the source's words

**Equation** (Eqs. 2-5 (X1 = ln DBH) and Table 3, Simple SUR, Lodgepole pine):

> Branch = exp(a31 + a32*X1); a31 = -3.384, a32 = 2.202

Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#equation

**Trees measured** (Materials and Methods, Data and Study Area):

> 22 Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) and 33 lodgepole pine (Pinus contorta) trees

Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#quote-fit-n-trees

**Our note:** Read from the author's accepted manuscript (draft, manuscript ID cjfr-2015-0256.R1), not the typeset article; values may differ from the final print. Fitted in original scale (nonlinear SUR), so no log back-transform correction. DBH in cm, biomass in kg (Eq. 2-5 text).  Extended SUR models using height and crown length are not included (crown length is not a canonical variable).

## 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 = 15 | 13.2 | 13.2 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 25 | 40.6 | 40.6 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 40 | 114 | 114 | Computed from the printed form: computed from the published form (coefficients as printed) |

Cite: https://treeallometry.org/equations/poudel-2016-lp-branch/#checks

The calculator on the page shows carbon as biomass × 0.47 (IPCC 2006 Guidelines, Vol. 4, Ch. 4, Table 4.3) and CO₂e as carbon × 44/12.

## How to cite

Cite the source for the equation: Poudel, K. P., & Temesgen, H. (2016). Methods for estimating aboveground biomass and its components for Douglas-fir and lodgepole pine trees. Canadian Journal of Forest Research, 46(1), 77-87. https://doi.org/10.1139/cjfr-2015-0256

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Lodgepole pine branch biomass, simple SUR (D only)", checked 2026-11-02, https://treeallometry.org/equations/poudel-2016-lp-branch/. 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/poudel-2016-lp-branch.json
Report a problem: email info@restorationscope.com with the equation id (poudel-2016-lp-branch) and where the right value appears.