Pursuant to the Endangered Species Act of 1973, as amended, we are required to designate critical habitat, to the maximum extent prudent and determinable, concurrent with a listing determination for a species. We are developing a listing determination for the Umtanum desert buckwheat and White Bluffs bladderpod as a separate rulemaking action (see RIN 1018-AX72). Umtanum desert buckwheat is a long-lived woody perennial plant that forms low mats. The species has an extremely slow growth rate, and individual plants may exceed 100 years of age. The only known population of the species, discovered in 1995, occurs on a wide mountain ridge in Benton County. White Bluffs bladderpod is a low-growing, herbaceous, perennial plant that lives 4 to 5 years. The species was first described in 1883 but was not recognized as a species at that time. The population was rediscovered in 1994 and was described as a species in 1996. Later work indicated that the plant may be a subspecies, and we regard it as such pending further information. The only known population of the subspecies is found primarily from cliff tops to near-vertical exposures of cemented, highly alkaline, caliche-like soil along a 10-mile strip of bluffs overlooking the Columbia River.