Index
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Characteristics of UN-Healthy Shrub Steppe
See before and after picture of WDFW Lands in the Methow Valley, showing the same area in the Spring (being grazed) and the fall (after grazing), 2007.
Invasive species dominate the area. Plants with an annual or rhizomatous phenology become relatively more common. The impact of invasive species is widely acknowledged, but more research is needed on understanding how it occurs. Quantitative documentation that could track these changes is very limited, but one such study is available from the Colville Indian Reservation (Klock). Even though the Reservation is in better overall condition than most other private lands in Okanogan county (personal observation), it has still been radically changed. These are Klock's conclusions: On the Colville Indian Reservation, nearly 300,000 acres of shrub-steppe cover approximately 1/3 of the area. A Soil Conservation Service range survey from the 1980s determined that 57% of the shrub-steppe on the Reservation was in poor condition, defined by having less than 25% of the site dominated by natives (Klock).
Reduced herbaceous cover, biomass, productivity and native species diversity (Coalition for Sonoran Desert Protection).
Grazing can remove the principal fuel used historically to carry grass fires.
Fire suppression contributes to the loss of grasslands and replacement with woody species (Coalition for Sonoran Desert Protection).
Native species may avoid grazed areas (Coalition for Sonoran Desert Protection).
Disease can spread from livestock to native ungulate populations (Coalition for Sonoran Desert Protection).
Fenced off riparian areas and downed barbed wire fence can impede wildlife access to riparian areas.
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