Astragalus pycnostachyus
Encyclopedia
Astragalus pycnostachyus is a species of milkvetch
known by the common name marsh milkvetch. It is endemic to the coastline of California
, where it grows in wet saline habitat such as marsh
es.
is a cluster of many whitish to greenish flowers each up to a centimeter in length.
The fruit is an inflated, papery legume pod with a small hooked beak at the tip.
, where one population of fewer than fifty individuals remain. Threats to its existence include near-total loss of habitat, infestation by weevil
s, cucumber mosaic virus
infection, competition from non-native plants such as ice plant, and herbivory by the milk snail
Otala lactea.
The single extant population of this rare plant variety is now fenced and protected. The variety is treated as an endangered species
on the federal level.
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 name marsh milkvetch. It is endemic to the coastline of 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 grows in wet saline habitat such as marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es.
Description
The marsh milkvetch is a perennial herb forming a thick erect clump of hollow, woolly stems 40 to 90 centimeters tall. The leaves are up to 15 centimeters long and are made up of many narrow 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 cluster of many whitish to greenish flowers each up to a centimeter in length.
The fruit is an inflated, papery legume pod with a small hooked beak at the tip.
Endangered Oxnard variety
There are two varieties. One, the Ventura marsh milkvetch (var. lanosissimus), exists only in Oxnard, CaliforniaOxnard, California
Oxnard is the 113th largest city in the United States, 19th largest city in California and largest city in Ventura County, California, by way of population. It is located at the western edge of the fertile Oxnard Plain, and is an important agricultural center, with its distinction as the...
, where one population of fewer than fifty individuals remain. Threats to its existence include near-total loss of habitat, infestation by weevil
Weevil
A weevil is any beetle from the Curculionoidea superfamily. They are usually small, less than , and herbivorous. There are over 60,000 species in several families, mostly in the family Curculionidae...
s, cucumber mosaic virus
Cucumber mosaic virus
Cucumber mosaic virus is a plant pathogenic virus in the family Bromoviridae.It is the type member of the plant virus genus, Cucumovirus. This virus has a worldwide distribution and a very wide host range. In fact it has the reputation of having the widest host range of any known plant virus...
infection, competition from non-native plants such as ice plant, and herbivory by the milk snail
Otala lactea
Otala lactea, common names, the milk snail, or Spanish snail, is a large, edible species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae. Archaeological recovery at the Volubilis illustrates prehistoric exploitation of O...
Otala lactea.
The single extant population of this rare plant variety is now fenced and protected. The variety is treated as an 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...
on the federal level.