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): M. M. Dudley; N. A. Tisserat; W. R. Jacobi; J. Negron; J. E. Stewart
    Date: 2020
    Source: Forest Ecology and Management. 468: 118168.
    Publication Series: Scientific Journal (JRNL)
    Station: Rocky Mountain Research Station
    PDF: Download Publication  (2.0 MB)


    Historically, Cytospora canker of quaking aspen was thought to be caused primarily by Cytospora chrysosperma. However, a new and widely distributed Cytospora species on quaking aspen was recently described (Cytospora notastroma Kepley & F.B. Reeves). Here, we show the relative pathogenicity, abundance, and frequency of both species on quaking aspen in portions of the Rocky Mountain region, and constructed species-level phylogenies to examine possible hybridization among species. We inoculated small-diameter aspen trees with one or two isolates each of C. chrysosperma and C. notastroma in a greenhouse and in environmental growth chambers. Results indicate that both Cytospora species are pathogenic to drought-stressed aspen, and that C. chrysosperma is more aggressive (i.e., caused larger cankers) than C. notastroma, particularly at cool temperatures. Neither species cause significant canker growth on trees that were not drought-stressed. Both C. chrysosperma and C. notastroma are common on quaking aspen, in addition to a third, previously described species, Cytospora nivea. Multiple Cytospora species often co-occur on the same host tree, and evidence of hybridization among species exists.

    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.


    Dudley, M. M.; Tisserat, N. A.; Jacobi, W. R.; Negron, J.; Stewart, J. E. 2020. Pathogenicity and distribution of two species of Cytospora on Populus tremuloides in portions of the Rocky Mountains and midwest in the United States. Forest Ecology and Management. 468: 118168.


    Google Scholar


    Cytospora canker, quaking aspen, Populus tremuloides, pathogenicity

    Related Search

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