THE JEFFERSON COUNTY LAND BRIEF
Land in the
Deschutes River Valley setting.
Jefferson County has 1,781.7 square miles of land in Oregon. 8 mapped landscape regions meet across Jefferson County: Deschutes River Valley, John Day/Clarno Uplands, Ponderosa Pine/Bitterbrush Woodland, among others.
The Blue Mountains combine open mountain ranges and dissected volcanic uplands. The Wallowa and Elkhorn high country includes older granitic and metamorphic rocks above the surrounding lava landscape.
Regional context: Blue Mountains ↗ · Regional mapping across the county footprint
Where the landscape changes
Jefferson County intersects 8 mapped regional units. The largest mapped shares are:
- Deschutes River Valley32.5%
- John Day/Clarno Uplands30.4%
- Ponderosa Pine/Bitterbrush Woodland20.2%
- Cascade Crest Montane Forest8.6%
- John Day/Clarno Highlands4.7%
Eastern Cascades Slopes and Foothills in Jefferson County
On the Cascades' drier eastern side, open pine forests mingle with volcanic cones, buttes and basins. Larger river valleys and lake basins interrupt the surrounding uplands.
Read the regional source ↗Cascades in Jefferson County
Volcanic mountains, deeply cut stream valleys and glaciated high country define the Cascades. Conifer forests change with elevation, giving way to mountain meadows and rocky alpine terrain.
Read the regional source ↗Finding your parcel within Jefferson County
The atlas lists 6 cities, towns, townships, and Census communities associated with Jefferson County, including Warm Springs, Crooked River Ranch, Madras. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Jefferson County by land and water
The Census records 10.1 square miles of water within Jefferson County, or 0.6% of its total area. That share is close to Jefferson County’s 0.6%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Jefferson County has 218.3 times the land area of nearby Madras city (8.16 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Crook County, Deschutes County, Linn County, Marion County, Wasco County, Wheeler County within Oregon. A tract near one of these lines should be matched to the county identifier on its own records.

