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    Author(s): Mailea R. Miller-Pierce; Evan L. Preisser; Dave A. Orwig
    Date: 2009
    Source: In: McManus, Katherine A; Gottschalk, Kurt W., eds. Proceedings. 20th U.S. Department of Agriculture interagency research forum on invasive species 2009; 2009 January 13-16; Annapolis, MD. Gen. Tech. Rep. NRS-P-51. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 88.
    Publication Series: Other
    Station: Northern Research Station
    PDF: View PDF  (120.37 KB)


    While invasive species themselves have been examined, little work has addressed the question of competition between two invasive specialists on a shared host. An example of this situation exists in the eastern United States, where eastern hemlock (Tsuga canadensis) forests are threatened by two invasive herbivores: the elongate hemlock scale Fiorinia externa (EHS) and the hemlock woolly adelgid Adelges tsugae (HWA).

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    Miller-Pierce, Mailea R.; Preisser, Evan L.; Orwig, Dave A. 2009. The foliar chemistry dynamic in eastern hemlock and how it relates to the competitive mechanism between two invasive herbivores: Adelges tsugae and Fiorinia externa.

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