Astragalus lentiginosus
Encyclopedia
Astragalus lentiginosus is a species of legume
known by the common name
s spotted locoweed and freckled milkvetch. It is native to western North America
where it grows in many habitat types. There are a great number of wild varieties of this species, and they vary in appearance. The flower and the fruit of a given individual are generally needed to identify it down to the variety.
, east to the California Coast Ranges, south to northern Mexico
, and north to southern British Columbia
. The varieties are largely limited to marginal habitats such as disturbed sites in the arid regions of the continent. The group also contains a number of edaphic
specialists which occur at desert seeps which frequently exhibit high levels of calcium carbonate
.
holds up to 50 pea-like flowers which may be purplish or whitish or a mix of both. A unifying character among most of the varieties is an inflated, beaked legume pod with a groove along the side. The pod dries to a papery texture and dehisces
starting at the beak to release the seeds. The epithet lentiginosus refers to the red mottling commonly found on the pods which resemble freckles.
was the first to recognize the similarities among these taxa and arranged them as varieties of one species. Per Axel Rydberg
employed a very different species concept stating that he did not believe in infrataxa
This resulted in his raising Jones's varieties to species in the genera Cystium and Tium. A notable novelty of Rydberg's treatment is the concept of sections which have been maintained in the keys of subsequent treatments, even if this was not explicitly stated.
Subsequent treatments include Barneby, Isely, and Welsh. Each of these treatments are slightly different, containing between 36 and 42 taxa. Recent molecular work seems to suggest a genetic component to the varieties.
; var. coachellae is endangered
and var. piscinensis is threatened.
of the seed coat in order for the embryo to absorb water.
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
known by the common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
s spotted locoweed and freckled milkvetch. It is native to western North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
where it grows in many habitat types. There are a great number of wild varieties of this species, and they vary in appearance. The flower and the fruit of a given individual are generally needed to identify it down to the variety.
Distribution
As a species, Astragalus lentiginosus is distributed throughout the North American continent, west of the Rocky MountainsRocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...
, east to the California Coast Ranges, south to northern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, and north to southern British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
. The varieties are largely limited to marginal habitats such as disturbed sites in the arid regions of the continent. The group also contains a number of edaphic
Edaphic
Edaphic is a nature related to soil. Edaphic qualities may characterize the soil itself, including drainage, texture, or chemical properties such as pH. Edaphic may also characterize organisms, such as plant communities, where it specifies their relationships with soil...
specialists which occur at desert seeps which frequently exhibit high levels of calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
.
Description
Astragalus lentiginosus is a perennial or occasionally annual herb with leaves up to 15 centimeters long divided into many pairs of small leaflets. The plant is prostrate to erect in form and quite woolly to nearly hairless. 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...
holds up to 50 pea-like flowers which may be purplish or whitish or a mix of both. A unifying character among most of the varieties is an inflated, beaked legume pod with a groove along the side. The pod dries to a papery texture and dehisces
Dehiscence (botany)
Dehiscence is the opening, at maturity, in a pre-defined way, of a plant structure, such as a fruit, anther, or sporangium, to release its contents. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent...
starting at the beak to release the seeds. The epithet lentiginosus refers to the red mottling commonly found on the pods which resemble freckles.
Taxonomy
Many of what we currently know as varieties of Astragalus lentiginosus were originally described as individual species. Botanist Marcus E. JonesMarcus E. Jones
Marcus E. Jones was an American geologist, mining engineer and botanist. Throughout his career he was known for being an educator, scientist and minister. As an early explorer of the western United States he is known as the authority for numerous vascular plants. Much of his career was spent...
was the first to recognize the similarities among these taxa and arranged them as varieties of one species. Per Axel Rydberg
Per Axel Rydberg
Per Axel Rydberg was a Swedish-born, American botanist who was the first curator of the New York Botanical Garden Herbarium. -Biography:...
employed a very different species concept stating that he did not believe in infrataxa
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
This resulted in his raising Jones's varieties to species in the genera Cystium and Tium. A notable novelty of Rydberg's treatment is the concept of sections which have been maintained in the keys of subsequent treatments, even if this was not explicitly stated.
Subsequent treatments include Barneby, Isely, and Welsh. Each of these treatments are slightly different, containing between 36 and 42 taxa. Recent molecular work seems to suggest a genetic component to the varieties.
Varieties
Currently the following 40 taxa are recognized:- A. l. var. albifolius M.E.Jones 1923.
- A. l. var. ambiguus Barneby 1964.
- A. l. var. antonius Barneby 1945.
- A. l. var. araneosus (E.Sheld.) Barneby 1945.
- A. l. var. australis Barneby 1945.
- A. l. var. borreganus M.E.Jones 1898.
- A. l. var. chartaceus M.E.Jones 1895.
- A. l. var. coachellae Barneby 1964.
- A. l. var. diphysus (A.Gray) M.E.Jones 1895.
- A. l. var. floribundus Gray 1865.
- A. l. var. fremontii (A.Gray 1857) S.Watson 1871.
- A. l. var. higginsii S.L.Welsh 1981.
- A. l. var. idriensis M.E.Jones 1902.
- A. l. var. ineptus (A.Gray) M.E.Jones 1923.
- A. l. var. kennedyi (Rydb.) Barneby 1945.
- A. l. var. kernensis (Jeps.) Barneby 1945.
- A. l. var. latus (M.E.Jones) M.E.Jones 1923.
- A. l. var. lentiginosus Barneby 1964.
- A. l. var. maricopae Barneby 1945.
- A. l. var. micans Barneby 1956.
- A. l. var. mokiacensis (A.Gray) M.E.Jones 1923.
- A. l. var. multiracemosus S.L.Welsh & N.D.Atwood 2007.
- A. l. var. negundo S.L.Welsh & N.D.Atwood 2007.
- A. l. var. nigricalycis M.E.Jones 1895.
- A. l. var. oropedii Barneby 1945.
- A. l. var. palans (M.E.Jones) M.E.Jones 1898.
- A. l. var. piscinensis Barneby 1977.
- A. l. var. pohlii S.L.Welsh & Barneby 1981.
- A. l. var. salinus (Howell) Barneby 1945.
- A. l. var. scorpionis M.E.Jones 1923.
- A. l. var. semotus Jeps. 1936.
- A. l. var. sesquimetralis (Rydb.) Barneby 1945.
- A. l. var. sierrae M.E.Jones 1923.
- A. l. var. stramineus (Rydb.) Barneby 1945.
- A. l. var. trumbullensis S.L.Welsh & N.D.Atwood 1981.
- A. l. var. ursinus (A.Gray) Barneby 1945.
- A. l. var. variabilis Barneby 1945.
- A. l. var. vitreus Barneby 1945.
- A. l. var. wilsonii (Greene) Barneby 1945.
- A. l. var. yuccanus M.E.Jones 1898.
Conservation
Two rare varieties endemic to California are federally listed under the Endangered Species ActEndangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
; var. coachellae is endangered
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...
and var. piscinensis is threatened.
Cultivation
Astragalus lentiginosus is currently not cultivated commercially. Propagation from seed requires scarificationScarification
Scarifying involves scratching, etching, burning, or superficially cutting designs, pictures, or words into the skin as a permanent body modification.In the process of body scarification, scars are formed by cutting or branding the skin...
of the seed coat in order for the embryo to absorb water.