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): Jose F. NegronJohn B. Popp
    Date: 2009
    Source: Western North American Naturalist. 69(4): 447-458.
    Publication Series: Scientific Journal (JRNL)
    Station: Rocky Mountain Research Station
    PDF: Download Publication  (821.0 KB)


    Dryocoetes confusus Swaine, the western balsam bark beetle, is an important bark beetle associated with Abies lasiocarpa (Hook.) Nutt. (subalpine fir) in western North America. Little information is available on the life cycle and ecology of this insect in Colorado. In this study in north central Colorado, we examined its flight periodicity, attack patterns, and life cycle in downed trees. Flight season, as indicated by pheromone-trap catches, began in early June. Peak flight was observed during early to mid-July. A second peak in flight was observed in some years, but its occurrence was not consistent. Preferred attack sites on downed trees were the underside or side of the log and through branch stubs. The life cycle for this beetle was completed in 2 years, consistent with earlier observations from British Columbia. Sex ratio was 1:1, but a higher percentage of males fly earlier in the season.

    Publication Notes

    • You may send email to 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.


    Negron, Jose F.; Popp, John B. 2009. The flight periodicity, attack patterns, and life history of Dryocoetes confusus Swaine (Coleoptera: Curculionida: Scolytinae), the western balsam bark beetle, in north central Colorado. Western North American Naturalist. 69(4): 447-458.


    Dryocoetes confusus, western balsam bark beetle, Abies lasiocarpa, subalpine fir, flight periodicity

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page