Chapter4 - Drought patterns in the conterminous United States and Hawaii.

Droughts are common in virtually all U.S. forests, but their frequency and intensity vary widely both between and within forest ecosystems (Hanson and Weltzin 2000). Forests in the Western United States generally exhibit a pattern of annual seasonal droughts. Forests in the Eastern United States tend to exhibit one of two prevailing patterns: random occasional droughts, typical of the Appalachian Mountains and of the Northeast, or frequent late-summer droughts, typical of the southeastern Coastal Plain and the eastern edge of the Great Plains (Hanson and Weltzin 2000).