THE SISKIYOU COUNTY LAND BRIEF
Land in the
Low Southern Cascades Mixed Conifer Forest setting.
Siskiyou County has 6,278.8 square miles of land in California. 22 mapped landscape regions meet across Siskiyou County: Low Southern Cascades Mixed Conifer Forest, Marble/Salmon Mountains-Trinity Alps, Western Klamath Low Elevation Forests, among others.
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.
Regional context: Cascades ↗ · Regional mapping across the county footprint
Where the landscape changes
Siskiyou County intersects 22 mapped regional units. The largest mapped shares are:
- Low Southern Cascades Mixed Conifer Forest15.5%
- Marble/Salmon Mountains-Trinity Alps10%
- Western Klamath Low Elevation Forests10%
- Modoc Lava Flows and Buttes7.5%
- Klamath River Ridges7.5%
Klamath Mountains/California High North Coast Range in Siskiyou County
Dissected ridges, valleys and foothills combine varied rock types with diverse conifer and hardwood forests. The Klamath and Siskiyou ranges differ geologically from the volcanic Cascades to the east.
Read the regional source ↗Eastern Cascades Slopes and Foothills in Siskiyou 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 ↗Finding your parcel within Siskiyou County
The atlas lists 21 cities, towns, townships, and Census communities associated with Siskiyou County, including Happy Camp, Yreka, Weed. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Siskiyou County by land and water
The Census records 69.2 square miles of water within Siskiyou County, or 1.1% of its total area. That share is close to Siskiyou County’s 1.1%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Siskiyou County has 12,144.6 times the land area of nearby Grenada CDP (0.52 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Del Norte County, Humboldt County, Modoc County, Shasta County, Trinity County within California. A tract near one of these lines should be matched to the county identifier on its own records.

