# North American taxa group: woodland juniper refit (Table 5 footnote 2)

Aboveground biomass equation for Woodland Cupressaceae, mostly juniper (Cupressus spp., Juniperus monosperma, J. occidentalis, J. osteosperma), United States, from Chojnacky et al. 2014. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

Fitted on Juniperus monosperma, Juniperus occidentalis, Juniperus osteosperma, and other species the source does not name here.

## 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-woodland-juniper-refit/#equation

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

```
Aboveground biomass = exp(-2.719 + 2.2598 * ln(DRC))
```

Inputs: DRC = Root collar / stem base diameter (cm).
The source's own form: exp(-2.719 + 2.2598 * ln(drc)), with drc in cm; output in kg.
Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Woodland Cupressaceae, mostly juniper (Cupressus spp., Juniperus monosperma, J. occidentalis, J. osteosperma) (mixed species), family Cupressaceae; conifer
- Where: United States (equations compiled from US and Canadian studies). Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#where
- Biomes: temperate, dryland
- Stand: mixed
- Method: Refit of the woodland Cupressaceae taxon after adding pseudodata from unpublished studies where drc was measured by the current FIA definition; no back-transform correction. Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#method
- Verification: read in the original source
- Last checked: 2026-11-03. Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#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-woodland-juniper-refit/#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-woodland-juniper-refit/#equation

**Equation** (Table 5 footnote 2, p. 140):

> [ln(biomass) = −2.7190 + 2.2598 ln(drc)]

Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#quote-expression

**Note** (Table 5 footnote 2, p. 140):

> predicted 10–36% higher, depending on diameter

Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#quote-notes

**Taxon** (Table 4, p. 138):

> Cupressaceae J. osteosperma Juniper, Utah 65 0.54 3

Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#quote-taxon

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

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

Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#quote-fit-cf

**Our note:** The authors' alternative to the woodland Cupressaceae equation, which they say 'seemed to predict low, possibly due to influence from early juniper diameter measurements'. It predicts 10–36% more, depending on diameter. The paper gives no n, range or R² for it. By root-collar diameter.

## 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 |
| --- | --- | --- | --- |
| DRC = 30 | 144 | 144 | Computed from the printed form: computed from the published form at drc = 30 cm |

Cite: https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/#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: woodland juniper refit (Table 5 footnote 2)", checked 2026-11-03, https://treeallometry.org/equations/chojnacky-2014-woodland-juniper-refit/. 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-woodland-juniper-refit.json
Report a problem: email info@restorationscope.com with the equation id (chojnacky-2014-woodland-juniper-refit) and where the right value appears.