Shrub Invasions of North American Semiarid Grasslands

  title={Shrub Invasions of North American Semiarid Grasslands},
  author={O. W. Van Auken},
  journal={Annual Review of Ecology, Evolution, and Systematics},
  • O. V. Auken
  • Published 5 January 2000
  • Environmental Science
  • Annual Review of Ecology, Evolution, and Systematics
▪ Abstract The composition and structure of the semiarid or desert grasslands of southwestern North America have changed over the past 150 y. Brushy or woody species in these communities have increased in density and cover. This increase in density of woody species is called brush encroachment because most of these species have been present in these communities at lower densities for thousands of years. The brushy or woody species were not introduced from other continents or from great… 

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