The camas pocket gopher is a Willamette Valley animal, full stop. All 658 Oregon records since 2000 fall in ten counties, and nine of them form a solid block down the valley floor, from Multnomah and Washington counties in the north through Yamhill, Polk, Benton, and Marion to Lane. Washington County leads with 199 reports, followed by Benton at 118 and Yamhill at 110. Tillamook County, on the coast side of the Coast Range, holds a single record, the only hint of the species outside the valley trough.
The monthly pattern tracks fresh digging. Reports run from April through October, when soft soil and growing plants bring mounds to the surface and make the gopher’s work easy to spot, then drop off as the ground hardens and observers stay home. Since this gopher is endemic to the valley (found nowhere else), every county record helps define the edge of its entire world. Report volume still follows farms, roads, and people, so treat the cluster as a floor for the range, not a ceiling.
