Hesperolinon congestum
Encyclopedia
Hesperolinon congestum, or Marin Dwarf Flax, is an annual herb
, which is known to occur only in San Mateo, San Francisco and Marin County, California
, USA
. This plant occurs chiefly on serpentine soil
s, especially in dry native bunch grasses, chaparral
or other grassland
s at elevations less than 200 meters. The flower
s are congested at the tips of the dichotomously branching stems. H. congestum is in flower between April and July. The outlook for this plant depends on survival of only about twenty small colonies
, most of which are not actively managed for protection, even though the species
is State and Federally listed as threatened. This species is also less commonly known as Marin Western Flax.
vary between five and fifteen centimeters in length, with linear leaves manifesting alternately. The leaves
are typically not planar and not clasping, and stipule
glands are well developed with red exudate. Inflorescence
s are dense, with cymes characteristically open and 0.5 to 8.0 millimeter pedicel
s somewhat thread-like and ascending. The flower has five hairy sepal
s, which are three to four millimeters in size, whose margins are minutely glandular. Five petal
s are widely spreading between three and eight millimeters in dimension. These pink to rose colored petal
s each manifest three minute scales at the inner base; stamen dimensions vary between 5.5 and 7.0 millimeters. There are five stamen
s, and anthers are pink to deep purple. There exist six ovary
chambers; the number of whitish styles is three. Fruit
s have a smooth surface exterior. Chromosomal
characterization is: n=18.
was the first to collect and characterize Marin Dwarf Flax in the year 1863 in Marin County, during a project conducted by the California Geological Survey
. Originally the new species was called Linum congestum by Asa Gray
, although he described it in the section Hesperolinon within the same publication in the year 1865. It was J.K. Small who conveyed the discrete genus Hesperolinon to this plant in 1907.
By 1925 Jepson designated the Hesperolinon genus as a sector of the genus Linum and described Hesperolinon congestum as a subspecies of L. californicum. In 1961 Helen K. Sharsmith produced a definitive study of Hesperolinon, with the result that this taxon
clearly merited genus standing; moreover, she also returned Marin Dwarf Flax, H. congestum to species status.
, Alice Eastwood
and Katharine Brandegee. Most of these early sightings were made in Tiburon
and San Francisco. In the mid 1900s recording arose in San Mateo County, principally in Redwood City (Edgewood Park
) and in San Mateo
has classified Marin Dwarf Flax: List 1B, R-E-D Code 3-3-3ru. In 2006 the Pacific Gas and Electric Company
announced a program that has the potential for further reducing the habitat and population of H. congestum and a number of other listed species. In these activities Pacific Gas and Electric announced it would destroy or modify over 500,000 acres (2,000 km²) of habitat in California, some of which is known habitat for H. congestum. It is indicated that a full Environmental Impact Report would be prepared for public review prior to any of the proposed actions. The most destructive element of this proposed program is the use of herbicide
to effect a kill of virtually all vegetation
in large areas of power line rights-of-way.
Ring Mountain
in Marin County, California
is a location of occurrence of H. congestum; in fact the sole population that is actively managed is found on Ring Mountain
, a nature reserve
on the Tiburon
Peninsula
managed by The Nature Conservancy
. Most of the present colonies are in San Mateo County; two of these in the vicinity of the Crystal Springs Reservoir
are in danger of destruction by an expanded trail
system proposed by the county. The proposed Jefferson-Martin 230 kV transmission line, (running from San Francisco to north San Mateo County, would traverse and impact known habitat of Marin Dwarf Flax.
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...
, which is known to occur only in San Mateo, San Francisco and Marin County, California
Marin County, California
Marin County is a county located in the North San Francisco Bay Area of the U.S. state of California, across the Golden Gate Bridge from San Francisco. As of 2010, the population was 252,409. The county seat is San Rafael and the largest employer is the county government. Marin County is well...
, USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. This plant occurs chiefly on serpentine soil
Serpentine soil
A serpentine soil is derived from ultramafic rocks, in particular serpentinite, a rock formed by the hydration and metamorphic transformation of ultramafic rock from the Earth's mantle....
s, especially in dry native bunch grasses, chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
or other grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
s at elevations less than 200 meters. The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are congested at the tips of the dichotomously branching stems. H. congestum is in flower between April and July. The outlook for this plant depends on survival of only about twenty small colonies
Colony (biology)
In biology, a colony reference to several individual organisms of the same species living closely together, usually for mutual benefit, such as stronger defense or the ability to attack bigger prey. Some insects live only in colonies...
, most of which are not actively managed for protection, even though the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
is State and Federally listed as threatened. This species is also less commonly known as Marin Western Flax.
Description
Stems of this wildflowerWildflower
A wildflower is a flower that grows wild, meaning it was not intentionally seeded or planted. Yet "wildflower" meadows of a few mixed species are sold in seed packets. The term "wildflower" has been made vague by commercial seedsmen who are interested in selling more flowers or seeds more...
vary between five and fifteen centimeters in length, with linear leaves manifesting alternately. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are typically not planar and not clasping, and stipule
Stipule
In botany, stipule is a term coined by Linnaeus which refers to outgrowths borne on either side of the base of a leafstalk...
glands are well developed with red exudate. Inflorescence
Inflorescence
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...
s are dense, with cymes characteristically open and 0.5 to 8.0 millimeter pedicel
Pedicel (botany)
A pedicel is a stem that attaches single flowers to the main stem of the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower....
s somewhat thread-like and ascending. The flower has five hairy sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s, which are three to four millimeters in size, whose margins are minutely glandular. Five petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s are widely spreading between three and eight millimeters in dimension. These pink to rose colored petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s each manifest three minute scales at the inner base; stamen dimensions vary between 5.5 and 7.0 millimeters. There are five stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s, and anthers are pink to deep purple. There exist six ovary
Ovary
The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...
chambers; the number of whitish styles is three. Fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s have a smooth surface exterior. Chromosomal
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
characterization is: n=18.
Taxonomy
Henry Nicholas BolanderHenry Nicholas Bolander
Henry Nicholas Bolander was a German-American botanist and educator.Bolander was born in Schlüchtern, Germany and emigrated to the United States in 1846. He joined his uncle in Columbus, Ohio and enrolled in the Columbus Lutheran Seminary. He graduated from the seminary and was ordained a...
was the first to collect and characterize Marin Dwarf Flax in the year 1863 in Marin County, during a project conducted by the California Geological Survey
California Geological Survey
Although it was not until 1880 that the California State Mining Bureau, predecessor to the California Geological Survey, was established, the "roots" of California's state geological survey date to an earlier time...
. Originally the new species was called Linum congestum by Asa Gray
Asa Gray
-References:*Asa Gray. Dictionary of American Biography. American Council of Learned Societies, 1928–1936.*Asa Gray. Encyclopedia of World Biography, 2nd ed. 17 Vols. Gale Research, 1998.*Asa Gray. Plant Sciences. 4 vols. Macmillan Reference USA, 2001....
, although he described it in the section Hesperolinon within the same publication in the year 1865. It was J.K. Small who conveyed the discrete genus Hesperolinon to this plant in 1907.
By 1925 Jepson designated the Hesperolinon genus as a sector of the genus Linum and described Hesperolinon congestum as a subspecies of L. californicum. In 1961 Helen K. Sharsmith produced a definitive study of Hesperolinon, with the result that this taxon
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...
clearly merited genus standing; moreover, she also returned Marin Dwarf Flax, H. congestum to species status.
Distribution
Widespread collection and recognition of the species was made in the late 19th and early 20th centuries by botanical pioneers W.L. JepsonWillis Linn Jepson
Willis Linn Jepson is known as California's most distinguished early botanist. He became interested in botany as a boy and explored adjacent regions. He had come in contact with various botanists before he entered college...
, Alice Eastwood
Alice Eastwood
Alice Eastwood was a Canadian American botanist. Born in Toronto, she moved to the United States at 14, and from age twenty to thirty, was a teacher in Denver, Colorado and taught herself botany. In 1890 she assumed a post in the herbarium at the California Academy of Sciences...
and Katharine Brandegee. Most of these early sightings were made in Tiburon
Tiburon
Tiburon may refer to:Places* Tiburon, California* Tiburón Golf Club Naples, Florida* Tiburón Island, an island in the Gulf of California* Tiburon Peninsula, a peninsula in the San Francisco Bay Area of California...
and San Francisco. In the mid 1900s recording arose in San Mateo County, principally in Redwood City (Edgewood Park
Edgewood Park
Edgewood Park can refer to:* Edgewood Park in New Haven, Connecticut* Edgewood Park & Natural Preserve, San Mateo County, California* Edgewood Park neighborhood in Fort Erie, Ontario* Edgewood Park neighborhood in Fort Wayne, Indiana...
) and in San Mateo
San Mateo, California
San Mateo is a city in San Mateo County, California, United States, in the San Francisco Bay Area. With a population of approximately 100,000 , it is one of the larger suburbs on the San Francisco Peninsula, located between Burlingame to the north, Foster City to the east, Belmont to the south,...
Conservation
The State of California classified Marin Dwarf Flax as a threatened species in the year 1992, and the Federal Government listed this plant as threatened in 1995. In addition to the state of California and U.S. federal government protected designations, the California Native Plant SocietyCalifornia Native Plant Society
The California Native Plant Society is a California not-for-profit organization that seeks to increase understanding of California's native flora and to preserve that flora. Its "paramount purpose is to preserve wild plants".-History:...
has classified Marin Dwarf Flax: List 1B, R-E-D Code 3-3-3ru. In 2006 the Pacific Gas and Electric Company
Pacific Gas and Electric Company
The Pacific Gas and Electric Company , commonly known as PG&E, is the utility that provides natural gas and electricity to most of the northern two-thirds of California, from Bakersfield almost to the Oregon border...
announced a program that has the potential for further reducing the habitat and population of H. congestum and a number of other listed species. In these activities Pacific Gas and Electric announced it would destroy or modify over 500,000 acres (2,000 km²) of habitat in California, some of which is known habitat for H. congestum. It is indicated that a full Environmental Impact Report would be prepared for public review prior to any of the proposed actions. The most destructive element of this proposed program is the use of herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
to effect a kill of virtually all vegetation
Vegetation
Vegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...
in large areas of power line rights-of-way.
Ring Mountain
Ring Mountain (California)
Ring Mountain is an elevated landform on the Tiburon Peninsula in Marin County, California. This mountain was named for George E. Ring, who served as a Marin County Supervisor from 1895 to 1903.A number of rare and endangered flora inhabit Ring Mountain...
in Marin County, California
Marin County, California
Marin County is a county located in the North San Francisco Bay Area of the U.S. state of California, across the Golden Gate Bridge from San Francisco. As of 2010, the population was 252,409. The county seat is San Rafael and the largest employer is the county government. Marin County is well...
is a location of occurrence of H. congestum; in fact the sole population that is actively managed is found on Ring Mountain
Ring Mountain (California)
Ring Mountain is an elevated landform on the Tiburon Peninsula in Marin County, California. This mountain was named for George E. Ring, who served as a Marin County Supervisor from 1895 to 1903.A number of rare and endangered flora inhabit Ring Mountain...
, a nature reserve
Nature reserve
A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...
on the Tiburon
Tiburon, California
Tiburon is an incorporated town in Marin County, California. It occupies most of the Tiburon Peninsula, which reaches south into the San Francisco Bay. The smaller city of Belvedere occupies the south-east part of the peninsula and is contiguous with Tiburon...
Peninsula
Peninsula
A peninsula is a piece of land that is bordered by water on three sides but connected to mainland. In many Germanic and Celtic languages and also in Baltic, Slavic and Hungarian, peninsulas are called "half-islands"....
managed by The Nature Conservancy
The Nature Conservancy
The Nature Conservancy is a US charitable environmental organization that works to preserve the plants, animals, and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive....
. Most of the present colonies are in San Mateo County; two of these in the vicinity of the Crystal Springs Reservoir
Crystal Springs Reservoir
Crystal Springs Reservoir is a pair of artificial lakes located in the northern Santa Cruz Mountains of San Mateo County, California situated in the rift valley created by the San Andreas Fault just to the west of the cities of San Mateo and Hillsborough, and I-280...
are in danger of destruction by an expanded trail
Trail
A trail is a path with a rough beaten or dirt/stone surface used for travel. Trails may be for use only by walkers and in some places are the main access route to remote settlements...
system proposed by the county. The proposed Jefferson-Martin 230 kV transmission line, (running from San Francisco to north San Mateo County, would traverse and impact known habitat of Marin Dwarf Flax.