''Swallenia'' is a rare genus of plants in the grass family, found only in

Death Valley National Park Death Valley National Park is a national park of the United States that straddles the California–Nevada border, east of the Sierra Nevada. The park boundaries include Death Valley, the northern section of Panamint Valley, the southern sect ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. The only known species is ''Swallenia alexandrae'', known by the common names Eureka dunegrass and Eureka Valley dune grass. This genus was named for American botanist Jason Richard Swallen (1903-1991). The species was named for American philanthropist and paleontological collector Annie Montague Alexander.

Description

This is a rare plant

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Inyo County, California Inyo County () is a County (United States), county in the Eastern California, eastern central part of the U.S. state of California, located between the Sierra Nevada and the state of Nevada. In the 2020 United States census, 2020 census, the po ...

, where it is found on a single isolated dune system, the Eureka Valley Sand Dunes in the Eureka Valley of the

Mojave Desert The Mojave Desert (; ; ) is a desert in the rain shadow of the southern Sierra Nevada mountains and Transverse Ranges in the Southwestern United States. Named for the Indigenous peoples of the Americas, indigenous Mohave people, it is located pr ...

, within Death Valley National Park.

Description

''Swallenia alexandrae'' is a coarse, tufted perennial grass which grows in sand from thick

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s. Its stiffly erect clums, sharp-leafed grass, and erect pale-colored panicle inflorescences are diagnostic.

Endangered status

This is a federally listed threatened species of the United States.Plant Conservation Report
/ref> The main threat to the species survival has been

off-roading Off-roading is the act of driving or riding in a vehicle on unpaved surfaces such as sand, dirt, gravel, riverbeds, mud, snow, rocks, or other natural terrain. Off-roading ranges from casual drives with regular vehicles to competitive events w ...

, which is no longer permitted in its

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

. Trespassing off-roaders and campers are still a threat to the five remaining occurrences.The Nature Conservancy
/ref>

References

External links

Calflora Database: ''Swallenia alexandrae'' (Eureka Valley dune grass, Eureka dunegrass)Jepson Manual treatment for Swallenia alexandraeGrass Manual Profile''Swallenia alexandrae'' — UC Photos gallery
Chloridoideae Monotypic Poaceae genera Native grasses of California Endemic flora of California Flora of the California desert regions Natural history of the Mojave Desert Natural history of Inyo County, California ~ Threatened flora of California {{Chloridoideae-stub