Pinon-juniper woodlands are an important vegetation type in the Great Basin. Old-growth and open shrub savanna woodlands have been present over much of the last several hundred years. Strong evidence indicates these woodlands have experienced significant tree infilling and major expansion in their distribution since the late 1800s by encroaching into surrounding landscapes once dominated by shrubs and herbaceous vegetation (fig. 1). Both infilling and expansion affects soil resources, plant community structure and composition, water and nutrient cycles, forage production, wildlife habitat, biodiversity, and fire patterns across the landscape. Another impact is the shift from historic fire regimes to larger and more intense wildfires that are increasingly determining the future of this landscape.
Tausch, R. J.; Miller, R. F.; Roundy, B. A.; Chambers, J. C. 2009. Pinon and juniper field guide: Asking the right questions to select appropriate management actions. U.S. Geological Survey Circular 1335. Reston, VA: U.S. Geological Survey. 96 p.