Question: The largest area of contiguous endorheic waterheds in North America is home to what common name of buckwheat?

Context paragraphs:
Eriogonum thurberi: Eriogonum thomasii is a species of wild buckwheat known by the common name Thurber's buckwheat.  It is native to the desert southwest of North America in Arizona, California, New Mexico and three desert states of Mexico, where it is common to abundant in many areas.

Eriogonum niveum: Eriogonum niveum is a species of flowering plant in the buckwheat family known by the common name snow buckwheat.  It is native to the Pacific Northwest of North America, where it occurs in British Columbia, Washington, Oregon, and Idaho.

Eriogonum ovalifolium: Eriogonum ovalifolium is a species of wild buckwheat known by the common name cushion buckwheat.  It is native to western North America from California to Alberta, where it is a member of many plant communities in varied habitats.

Great Basin Divide: The Great Basin Divide is the western continental divide that separates the Great Basin from the Pacific Ocean watershed.  The water divide is the perimeter of the largest set of contiguous endorheic watersheds of North America, including six entire USGS watershed subregions.  For example, the San Joaquin River subregion that drains to the Pacific is adjacent to the Great Basin's Mono-Northern Mojave subregion and central Lahontan subregion, and their triple point is on the Great Basin Divide.

Eriogonum strictum: Eriogonum strictum is a species of wild buckwheat known by the common name Blue Mountain buckwheat.  It is a common plant of western North America from northern California to British Columbia where it is found along rocky slopes and scrubland.

Buckwheat: Buckwheat ("Fagopyrum esculentum"), also known as common buckwheat, Japanese buckwheat and silverhull buckwheat, is a plant cultivated for its grain-like seeds and as a cover crop.  A related and more bitter species, "Fagopyrum tataricum", a domesticated food plant common in Asia, but not as common in Europe or North America is also referred to as buckwheat.

Eriogonum cernuum: Eriogonum cernuum is a species of wild buckwheat known by the common name nodding buckwheat.  It is native to much of western North America, where it grows in sandy and gravelly habitat, including woodland and sagebrush.  It is an annual herb growing up to about 60 centimeters in maximum height with a thin, branching flowering stem.  The rounded, woolly leaves are one or two centimeters wide and are mainly located about the base of the stem.  The inflorescence is evenly lined with hanging involucres of flowers.  The individual flowers are less than 2 millimeters wide and white to pink-tinged in color.

Great Basin: The Great Basin is the largest area of contiguous endorheic watersheds in North America.  It spans sections of Wyoming, Idaho, Utah, Nevada, Oregon, California and the Mexican state of Baja California.  It is noted for both its arid climate and the basin and range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than 100 mi away at the summit of Mount Whitney.  The region spans several physiographic divisions, biomes/ecoregions, and deserts.

List of Great Basin watersheds: The Great Basin is the largest region of contiguous endorheic drainage basins in North America, and is encompassed by the Great Basin Divide.  This is a list of the drainage basins in the Great Basin that are over 500 sqmi , listed by the state containing most of the basin.

Eriogonum pusillum: Eriogonum pusillum is a species of wild buckwheat known by the common name yellowturbans.  It is native to the western United States where it grows in sandy soils in a number of habitats, especially in the Mojave Desert and Great Basin.

Supporting paragraphs: Eriogonum pusillum Great Basin
Answer: yellowturbans