Astragalus clarianus
Encyclopedia
Astragalus clarianus is a rare species of milkvetch
known by the common names Clara Hunt's milkvetch and Napa milkvetch. It is endemic to northern California
where it is known from only four or five occurrences along the border between Sonoma
and Napa Counties
. It is a federally listed endangered species
.
is a small cluster of 2 to 7 flowers. Each flower is about a centimeter long and has white petals with bright deep purple tips. The fruit is a papery legume pod around 2 centimeters long. It is tapered at both ends, hairy in texture, and it bears a sharp beak at one end. The plant was named for the California schoolteacher and amateur botanist Clara Adele Pike Blodgett Hunt.
, urban development
, the establishment of vineyard
s in its habitat, grazing
, trampling, alterations in the water regime, recreation
, and road and airport
maintenance activities.
Astragalus
Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...
known by the common names Clara Hunt's milkvetch and Napa milkvetch. It is endemic to northern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
where it is known from only four or five occurrences along the border between Sonoma
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....
and Napa Counties
Napa County, California
Napa County is a county located north of the San Francisco Bay Area in the U.S. state of California. It is coterminous with the Napa, California, Metropolitan Statistical Area. As of 2010 the population is 136,484. The county seat is Napa....
. It is a federally listed endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
.
Description
This is an annual herb producing thin stems covered in tiny rough hairs. The plant reaches up to 12 centimeters tall. The small leaves are made up of a few pairs of oval-shaped leaflets. The inflorescenceInflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is a small cluster of 2 to 7 flowers. Each flower is about a centimeter long and has white petals with bright deep purple tips. The fruit is a papery legume pod around 2 centimeters long. It is tapered at both ends, hairy in texture, and it bears a sharp beak at one end. The plant was named for the California schoolteacher and amateur botanist Clara Adele Pike Blodgett Hunt.
Ecology
This rare plant faces several threats, including invasive speciesInvasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
, urban development
Urban planning
Urban planning incorporates areas such as economics, design, ecology, sociology, geography, law, political science, and statistics to guide and ensure the orderly development of settlements and communities....
, the establishment of vineyard
Vineyard
A vineyard is a plantation of grape-bearing vines, grown mainly for winemaking, but also raisins, table grapes and non-alcoholic grape juice...
s in its habitat, grazing
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...
, trampling, alterations in the water regime, recreation
Recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be "fun"...
, and road and airport
Airport
An airport is a location where aircraft such as fixed-wing aircraft, helicopters, and blimps take off and land. Aircraft may be stored or maintained at an airport...
maintenance activities.