Facts & Figures
Western Bluebird, Credit: J. Leonard
By the Numbers
10% Remains of Historic Oak & Prairie Range
Across the Pacific Northwest, oak and prairie communities historically occurred west of the Cascades from northern California to British Columbia but can now only be found on approximately 10% of its historic range.
Oregon
In Oregon, an estimated 25% of historic oak habitat remains and only 1% of native prairies.
Washington
In Washington, prairies are one of the state’s rarest ecosystems. with only 3% of historic prairies remaining.
British Columbia
In British Columbia, less than 5% of oak and prairie habitat remains in fragmented patches.
California
In California, a third of oak woodlands and forests have been lost to agriculture and urban development.
46 Species Imperiled
46 species that depend on oak and prairie systems are so imperiled they are legally regulated.
Lifeways of Indigenous People
Culturally important first foods, plant materials, and medicines foundational to the lifeways of Indigenous people are threatened by the loss of habitat and access.
100-200 Years to Regrow an Oak Woodland
Oak trees are very slow growing – it takes 100-200 years to regrow an oak woodland - and old trees provide the significant ecological function found in these ecosystems. Plants that grow in the understory are often displaced by weeds following excessive grazing or soil disturbance, making intact oak woodlands effectively irreplaceable.
Oaks in the Way of Development
Much remaining oak habitat occurs in the wildland-urban interface, putting oaks in the way of rural and urban development. As population growth accelerates, urban growth boundaries will expand.
By the Numbers Poster
Download, print and shareable this graphic.