Index
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What is healthy native shrub-steppe?
Excellent condition native shrub-steppe has been defined as having >75% cover of native late-seral shrub-steppe species (Klock, citing criteria from National Resources Conservation Service).
Predominance of co-evolved native shrub and grass species - sagebrush, bitterbrush, bluebunch wheatgrass, Sandberg bluegrass, hopsage (Grayia) saltbush (Atriplex). (Daubenmire).
Bunchgrass predominates, with few or no rhizomatous grasses present. This allows site occupancy by a diverse species mix (Brown and Seig).
Presence of spring ephemerals between grass clumps, e.g., biscuit-roots; mission bells, wild onions, etc, many of which were crucial to the survival of native American culture. "Indians managed this resource through the use of agriculture and controlled burning." (Turner).
Healthy native animal populations that provide ecosystem feedback controls. These may include obligate shrub-steppe species such as pygmy rabbits, sage and sharp-tailed grouse, or antelope. Mule deer co-evolution in shrub-steppe ecosystems is indicated by limiting bitterbrush winter forage that keeps mule deer populations in check and makes overgrazing unlikely.
"Well-managed livestock grazing on Department land in the Methow Wildlife Area has been used as a tool to decrease competition of bunchgrasses and increase growth, vigor, and regeneration of bitterbrush ... (WDFW)
Strategy: Permit light late summer domestic livestock grazing to remove dead grass material and stimulate new growth spring deer forage." (WDFW).
Cryptobiotic crust presence is an indicator of long-term ecosystem health; it provides nitrogen fixation, hydraulic conductivity and soil stabilization through protection from wind and raindrops (Belnap).
Ecotonal connectivity is maintained with adjacent forest and riparian systems (Gorman, many others).
Frequency of presettlement fire is still unclear; tenuous assumptions of 7-15 year fire return intervals from ponderosa pine scars conflict with determinations of longer intervals of up to 150-years (Welch and Criddle; Whisenant; Belnap).
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