Loch Lomond Vernal Pool Ecological Reserve is an 8.22-acre protected area in Loch Lomond, Lake County, California, managed within the state ecological reserve system. Its importance centers on a seasonal vernal pool that shelters the rare Loch Lomond button celery, first collected here in 1941 and long known only from this site. After proposed dredging and filling threatened the pool, the plant received federal endangered protection in 1985 and a final listing in 1987. The state bought the land in 1988 and added fencing to reduce damage. Once used for local recreation, the reserve also supports other rare vernal-pool plants in southern Lake County’s mountain landscape.