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): Frank H. KochJohn W. Coulston
    Date: 2020
    Source: Gen. Tech. Rep. SRS-250. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station
    Publication Series: General Technical Report (GTR)
    Station: Southern Research Station
    PDF: Download Publication  (14.0 MB)


    Although ecologists do not define the term “drought” consistently (Slette and others 2019), one definition that is applicable to forests is that a drought is a period of precipitation deficit that persists long enough to deplete available soil water, leading to impacts on trees and other plants; in some cases, these impacts include plant injury or death (Anderegg and others 2012, Hanson and Weltzin 2000). Under this definition, droughts affect most forests in the United States, but their frequency and intensity vary considerably between geographic regions (Hanson and Weltzin 2000). These variations define the regions’ predominant drought regimes. Most forests in the Western United States are subject to seasonal droughts on a yearly basis. By comparison, forests in the Eastern United States usually exhibit one of the following drought patterns: random (i.e., occurring at any time of year) occasional droughts, as usually observed in the Appalachian Mountains and the Northeast, or frequent late-summer droughts, as usually observed in the Southeastern Coastal Plain and the eastern portion of the Great Plains (Hanson and Weltzin 2000).

    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.


    Koch, Frank H.; Coulston, John W. 2020. Chapter 4 - Drought and moisture surplus patterns in the conterminous United States: 2018, 2016– 2018, and 2014–2018. In: Potter, Kevin M.; Conkling, Barbara L., eds. Forest health monitoring: national status, trends, and analysis 2019. Gen. Tech. Rep. SRS-250. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station: 83-102.

    Related Search

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