''Eriogonum umbellatum'' is a species of
wild buckwheat known by the common name sulphurflower buckwheat, or simply sulphur flower.
Description
It is an extremely variable plant and hard to identify because individuals can look very different from one another. Also, there are many varieties. It may be a perennial herb blooming by summer
with stems tall and two to six clusters of flowers, with a whorl of leaves below the stems,
or a sprawling
shrub
A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...
approaching high and wide. The leaves are usually woolly and low on the plant, and the flowers come in many colors from white to bright yellow to purple.
Varieties
*''E. u.'' var. ''argus'' - often nearly hairless leaves and bright yellow flowers; limited to the
Klamath Mountains
*''E. u.'' var. ''dichrocephalum'' - found throughout much of the western United States
*''E. u.'' var. ''furcosum'' - a low shrub native to the
Sierra Nevada
The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...
*''E. u.'' var. ''glaberrimum'' - (green buckwheat) - a nearly hairless, white-flowered species
*''E. u.'' var. ''humistratum'' - (Mt. Eddy buckwheat) - a rare northern California
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 ...
*''E. u.'' var. ''juniporinum'' - (juniper buckwheat) - an uncommon plant of eastern California and western Nevada
*''E. u.'' var. ''subalpinum'' - (sulfur buckwheat) - similar to ''Eriogonum eriogonum'' but has wider and more spoon-shaped leaves
*''E. u.'' var. ''torreyanum'' - (Donner Pass buckwheat) - known from fewer than 10 occurrences near the
Donner Pass
*''E. u.'' var. ''versicolor'' - bears pinkish-brown flowers with bright stripes
Distribution and habitat
It is native to western North America from
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 ...
to
Colorado
Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...
to central Canada, where it is abundant and found in many habitats, including the
sagebrush steppe and alpine areas.
Ecology
It is a popular larval host, feeding the
bramble hairstreak,
desert green hairstreak,
lupine blue,
Mormon metalmark,
Rocky Mountain dotted blue,
Sheridan's hairstreak,
Sonoran metalmark, and
western green hairstreak. Additionally, goats and domestic sheep feed on the plant.
Cultivation
The wildflower gardening author Claude A. Barr complemented sulphurflower buckwheat as a "treasure in appearance and in adaptation in my garden."
It is valued for its very low water usage for
xeriscaping
Xeriscaping is the process of Garden design, landscaping, or gardening, that reduces or eliminates the need for irrigation. It is promoted in regions that do not have accessible, plentiful, or reliable supplies of fresh water and has gained acce ...
. The cultivar "Kannah Creek", a selection of ''Eriogonum umbellatum'' var. ''aureum'', has been introduced to the garden trade by the Plant Select cooperative sponsored by Colorado State University and Denver Botanic Gardens.
It grows in
USDA zones 4–8.
References
External links
*
Jepson Manual TreatmentEthnobotanyPhoto gallery
{{Taxonbar, from=Q280299
umbellatum
Flora of the Northwestern United States
Flora of the Southwestern United States
Flora of Alberta
Flora of British Columbia
Flora of New Mexico
Flora of the Cascade Range
Flora of the Rocky Mountains
Flora of the Sierra Nevada (United States)
Flora of the California desert regions
Natural history of the California chaparral and woodlands
Natural history of the California Coast Ranges
Natural history of the Mojave Desert
Natural history of the Peninsular Ranges
Natural history of the San Francisco Bay Area
Natural history of the Transverse Ranges