Carex albida is a very rare species of sedge known by the common name white sedge. It is endemic to Sonoma County, California, where it is known only from one occurrence at Pitkin Marsh, a wetland between Forestville and Sebastopol. There are fewer than 1000 plants remaining, and likely fewer than 300 according to more recent estimates. It is a federally listed endangered species. Carex albida has been found to be part of the more common and previously identified species Carex lemmonii. This sedge occurs near another rare local endemic, the Pitkin Marsh lily (Lilium pardalinum ssp. pitkinense).