Expansion of woodlands into sagebrush (Artemisia spp.) ecosystems is characterized by an inverse relationship of an increasing tree overstory and decreasing shrub and herbaceous understory. The time it takes woodlands to go from the very early to late successional stages (see discussion of Phase I to Phase III woodlands) is largely determined by the key components of the ecological site (climate, soils, topography), disturbance history, and seed source. The shift from sagebrush-dominated ecosystems to woodlands influences water, energy, and nutrient cycles; C and N pools; and disturbance regimes, wildlife habitat, resilience, and resistance to invasive species.
For more detailed information and citations refer to: Miller, R.F. and others. 2019. The Ecology, History, Ecohydrology, and Management of Pinyon and Juniper Woodlands in the Great Basin and Northern Colorado Plateau of the Western U.S. US Forest Service, Rocky Mountain Research Station. RMRS-GTR-403. 284 pg.