Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Justin S. Crotteau; Christopher R. Keyes; Sharon M. Hood; David L. R. Affleck; Anna Sala
    Date: 2018
    Source: Fire Ecology. 14(2): 165-.
    Publication Series: Scientific Journal (JRNL)
    Station: Pacific Northwest Research Station
    PDF: View PDF  (794.0 KB)

    Description

    Background: Fuel reduction treatments have been widely implemented across the western US in recent decades for both fire protection and restoration. Although research has demonstrated that combined thinning and burning effectively reduces crown fire potential in the few years immediately following treatment, little research has identified effectiveness of thinning and burning treatments beyond a decade. Furthermore, it is unclear how posttreatment disturbances such as a bark beetle outbreak affect fuel treatment effectiveness.

    Results: We evaluated differences in surface and canopy fuel characteristics and potential fire behavior metrics between fuel reduction treatments (no-action or control, burn-only, thin-only, thin+burn) implemented in ponderosa pine (Pinus ponderosa Lawson & C. Lawson)−Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco)-dominated forests that were subsequently affected by a mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak after treatment. Experimental units were measured in 2002 (immediately following fuel treatment) and in 2016 (14 years after treatment and at least 4 years following a beetle outbreak). We found that beetle-altered thinning treatments (thin-only and thin+burn combined) had less fuel (i.e., 34% and 83% lower fine and coarse woody debris loading, respectively) and lower crown fire potential (i.e., 47% lower probability of torching and 42% greater crowning index) than corresponding unthinned treatments (control and burn-only). There was no post-beetle-outbreak effect of burning treatments (burn-only and thin+burn combined) on surface fuel loading, but burning reduced crown fire potential (i.e., 37% greater crowning index) over unburned units (control and thin-only) 14 years after treatment. Additionally, we determined the relative impacts of fuel treatments and the bark beetle outbreak on fuel and crown fire potential differences and found that bark beetle-caused tree mortality inflated differences between controls and thinned treatments (thin-only and thin+burn) for surface fuel loading and probability of torching, but diminished differences between these treatments for canopy fuel loading, canopy bulk density, and crowning index.

    Conclusions: Despite the differential effects of bark beetle-caused tree mortality in the treatments, our study suggests that the effects of fuel treatments on mitigating crown fire potential persist even after a stand-transforming insect outbreak, especially when thinning and burning are combined.

    Publication Notes

    • You may send email to pnw_pnwpubs@fs.fed.us to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

    Citation

    Crotteau, Justin S.; Keyes, Christopher R.; Hood, Sharon M.; Affleck, David L. R.; Sala, Anna. 2018. Fuel dynamics after a bark beetle outbreak impacts experimental fuel treatments. Fire Ecology. 14(2): 165-. https://doi.org/10.1186/s42408-018-0016-6.

    Cited

    Google Scholar

    Keywords

    Dendroctonus ponderosae, disturbance interaction, fire and fire surrogate study, fuel dynamics, mediation analysis, Pinus ponderosa, Pseudotsuga menziesii, treatment longevity.

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/57736