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): Randall S. MorinAndrew M. Liebhold
    Date: 2016
    Source: Forestry. 89: 284-289.
    Publication Series: Scientific Journal (JRNL)
    Station: Northern Research Station
    PDF: Download Publication  (422.0 KB)


    Disturbanceby non-native insect species can be an important ecological driver shaping long-term changes in vegetation and plant species composition. While impacts of gypsy moth (Lymatria dispar L.) outbreaks in North American forests have been extensively studied, the results are quite inconsistent, particularly with respect to the amount of tree mortality associated with defoliation. In this study, we integrate geographical data describing historical gypsy moth defoliation with forest inventory data collected by a national forest inventory programme to quantify regional impacts across several million hectares of forest land in the northeastern US. While observed increases in host tree mortality rates and decreases in growth rates associated with defoliation were expected, the study also indicates that this overstory mortality, coupled with ongoing declines in oak regeneration, will result in a long-term reduction of oak density in defoliated areas. Eventually, these impacts will likely contribute to regional shifts in tree species composition and forest succession pathways. Gypsy moth outbreaks thus appear to exacerbate ongoing declines in young oak age classes in the region.

    Publication Notes

    • Check the Northern Research Station web site to request a printed copy of this publication.
    • Our on-line publications are scanned and captured using Adobe Acrobat.
    • During the capture process some typographical errors may occur.
    • Please contact Sharon Hobrla, if you notice any errors which make this publication unusable.
    • 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.


    Morin, Randall S.; Liebhold, Andrew M. 2016. Invasive forest defoliator contributes to the impending downward trend of oak dominance in eastern North America. Forestry. 89: 284-289.


    Google Scholar


    Lymantria dispar, gypsy moth, invasive pest, growth and mortality rates

    Related Search

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