# North American taxa group: Fagaceae, deciduous (Table 5)

Aboveground biomass equation for Fagaceae, United States, from Chojnacky et al. 2014. DBH 3–89 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Chojnacky et al. 2014 (Table 5 caption, p. 140):

> ln(biomass) = β0 + β1 ln(diameter)

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#equation

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

```
Aboveground biomass = exp(-2.0705 + 2.441 * ln(D))
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: exp(-2.0705 + 2.441 * ln(dbh)), with dbh in cm; output in kg.
Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Fagaceae (family), family Fagaceae; broadleaf
- Where: United States (equations compiled from US and Canadian studies). Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#where
- Biomes: temperate
- Stand: mixed
- DBH range: 3–89 cm. Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#dbh
- R²: 0.84. Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#r2
- Method: Weighted regression of ln(biomass) on ln(dbh) fitted to 606 pseudodata points generated from 77 published equations; no back-transform correction. Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#method
- Verification: read in the original source
- Last checked: 2026-11-01. Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#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

Chojnacky, D.C., Heath, L.S., Jenkins, J.C. (2014). Updated generalized biomass equations for North American tree species. Forestry, 87(1), 129–151.

- DOI: https://doi.org/10.1093/forestry/cpt053
- Access: open access
- Copy we read: https://research.fs.usda.gov/download/treesearch/45402.pdf
- Every equation from this source: https://treeallometry.org/sources/chojnacky-2014/
- Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#source

## The facts, in the source's words

**Equation** (Table 5 caption, p. 140):

> ln(biomass) = β0 + β1 ln(diameter)

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#equation

**Equation** (Table 5 row, p. 140):

> Fagaceae, deciduous 0.57 −2.0705 2.4410 606 77 dbh 3–89 0.84

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#quote-expression

**Taxon** (Table 3, p. 137):

> Quercus alba Oak, white 802 0.60 14 3 –74

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#quote-taxon

**Correction factor** (Methods, p. 139):

> we did not include a correction (Baskerville, 1972) for underestimation

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#quote-fit-cf

**Our note:** Deciduous oaks, beech and chestnut, including white oak (Q. alba, spg 0.60) and northern red oak (Q. rubra, spg 0.56). Median specific gravity of the group: 0.57. Diameter range is that of the pseudodata. R² is the published 'R²-statistic'.

## 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 = 30 | 509 | 509 | Computed from the printed form: computed from the published form at dbh = 30 cm |

Cite: https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/#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: Chojnacky, D.C., Heath, L.S., Jenkins, J.C. (2014). Updated generalized biomass equations for North American tree species. Forestry, 87(1), 129–151. https://doi.org/10.1093/forestry/cpt053

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "North American taxa group: Fagaceae, deciduous (Table 5)", checked 2026-11-01, https://treeallometry.org/equations/chojnacky-2014-fagaceae-deciduous/. 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/chojnacky-2014-fagaceae-deciduous.json
Report a problem: email info@restorationscope.com with the equation id (chojnacky-2014-fagaceae-deciduous) and where the right value appears.
