Tásmam Koyóm

Tásmam Koyóm is the Maidu name for the valley that is located in Plumas County, California. This valley was an important Maidu population center within the traditional homeland of the Mountain Maidu for many generations. When Euromerican settlers came to the area, they named it Humbug Valley and established the now-abandoned town of Longville.

Tásmam Koyóm consists of approximately 2,325 acres, which includes most of the Tásmam Koyóm alpine valley (excluding a private inholding) and certain adjacent hillside forest land. It is contained within four parcels, which are currently used as open spaces with dispersed recreational activities. The valley is located in northwestern Plumas Country.

The northwest-trending valley floor contains an alpine meadow that is fairly level with sloping upland forest along the valley edges. Yellow Creek enters the valley at the northwest end and flows southerly exiting the valley through a narrow gorge as it flows toward the North Fork of the Feather River. Humbug Creek and Willow Creek are tributaries to Yellow Creek that empty into the valley from the northeast. The valley contains approximately 1,392 acres of meadow and riparian communities on the valley floor and along the creeks. The remaining 933 acres along the edges of the valley are forested. Approximately 136 acres of the forested portions of the property have been burned and salvage logged, while the remaining 797 acres contain mixed conifer forest. The elevation of the valley ranges between 4,265 and 4,825 feet above sea level.

Prior to Euroamerican settlement within Tásmam Koyóm, the land was held in common by the Mountain Maidu people. There were several villages along the western edge of the valley, and the Maidu community flourished in Tásmam Koyóm for thousands of years.