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): Rachael A. Sitz; Marcelo M. Zerillo; Jacob Snelling; Jorge Ibarra Caballero; Kathleen Alexander; Kendra Nash; Ned A. Tisserat; Whitney S. Cranshaw; Jane E. Stewart
    Date: 2018
    Source: Arboriculture and Urban Forestry. 43(3): 146-153.
    Publication Series: Scientific Journal (JRNL)
    Station: Rocky Mountain Research Station
    PDF: Download Publication  (1.0 MB)


    Drippy blight is an emergent disease of red oaks, caused by the interaction between a kermes scale insect (Allokermes galliformis) and a bacterium (Lonsdalea quercina subsp. quercina). Multi-locus sequence analysis was used to confirm the bacterial pathogen’s identity and its relationship to other phylogenetically related Enterobacteriaceae species. Further, Koch’s postulates were performed on sapling red oaks. Prior to the discovery of drippy blight disease in Colorado, in the United States, the bacterium was reported on oak trees in California but was limited to acorn infections. The scale insect, A. galliformis, was previously known to occur on pin oak in the eastern United States but was not previously associated with either this bacterium or the production of significant branch dieback associated with drippy blight. In addition to a description of this new disease, this research documents a host range expansion of L. quercina subsp. quercina to northern red oak (Quercus rubra), Shumard oak (Q. shumardii), and pin oak (Q. palustris) and extends the reported host range of A. galliformis to include northern red and Shumard oaks.

    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.


    Sitz, Rachael A.; Zerillo, Marcelo M.; Snelling, Jacob; Caballero, Jorge Ibarra; Alexander, Kathleen; Nash, Kendra; Tisserat, Ned A.; Cranshaw, Whitney S.; Stewart, Jane E. 2018. Drippy blight, a disease of red oaks in Colorado, U.S., produced from the combined effect of the scale insect Allokermes galliformis and the bacterium Lonsdalea quercina subsp. quercina. Arboriculture and Urban Forestry. 43(3): 146-153.


    Allokermes galliformis, Bacteria, Colorado, drippy blight, Lonsdalea quercina, red oak, scale insect

    Related Search

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