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Hickman's potentilla

2007 Schools Wikipedia Selection. Related subjects: Plants

                iPotentilla hickmanii
   Hickman's potentilla. Photo credit: Tony Morosco
   Hickman's potentilla. Photo credit: Tony Morosco

                             Conservation status

   Endangered (EN)
              Scientific classification

   Kingdom:   Plantae
   Division:  Magnoliophyta
   Class:     Magnoliopsida
   Order:     Rosales
   Family:    Rosaceae
   Subfamily: Rosoideae
   Genus:     Potentilla
   Species:   P. hickmanii

                                Binomial name

   Potentilla hickmanii
   Eastw., 1900

   Hickman’s potentilla (Potentilla hickmanii) is an endangered perennial
   herb of the rose family. This rare plant species is found in a narrowly
   restricted range in coastal northern California, primarily along a
   confined location of northern Monterey County, secondarily in extremely
   small colonies in San Mateo County and Sonoma County. This small
   wildflower, endemic to western slopes of the outer coastal range along
   the Pacific Ocean coast , produces bright yellow blossoms throughout
   the spring. The species is also known by the common name Hickman's
   cinquefoil.

   This plant, along with many other threatened species in the northern
   California Floristic Province, has been designated as a species
   meriting protection by the U.S. Government, State of California, local
   governments and private conservation groups. These designations have
   led to blueprints for protection of Hickman's potentilla in the form of
   official endangerment classifications and a species Recovery Plan, the
   latter promulgated by the U.S. Environmental Protection Agency. Even
   with all these efforts, the total current population is estimated to be
   fewer than 4500 organisms.

Description

   Hickman's Potentilla is found on Montara Mountain below 135 meters in
   elevation, at the extreme east (right) of this image.
   Enlarge
   Hickman's Potentilla is found on Montara Mountain below 135 meters in
   elevation, at the extreme east (right) of this image.

   Hickman’s potentilla is a rosetted non- glandular flowering plant with
   a thick taproot. It has a stem that is prostrate to decumbent, of
   variable length five to forty five centimeters, which may occur in a
   glabrous manifestation. Blooming occurs between April and June; in
   winter, the plant dies back enitrely, leaving only its woody stem
   intact. The hypanthium is three to six millimeters wide, with yellow
   obchordate petals six to eleven millimeters in length. Up to ten
   inflorescences may present in a single organism. Filaments are
   typically 1.5 to 4.0 millimeters in length, while anthers are only
   about one millimeter in size; moreover, the pistils generally number
   about ten and the slender styles are about two to three millimeters
   long.

   The somewhat subglabrous leaves are pinnately compound into generally
   six paired, palmately cleft leaflets. These basal leaves range from six
   to twenty five millimeters in length with individual leaflets two to
   eight millimeters long and about two millimeters wide. There are four
   to seven leaflets per side, in a separated or overlapped configuration.
   The leaflets are wedge-shaped, typically having three to four teeth
   (lobes) and originate from about halfway along the leaf stem. The
   smooth fruits are approximately two millimeters in diameter, and
   normally occur as tan in colour.

Range and habitat

   Coastal habitat near the vicinity of Vicente Creek, Moss Beach
   Enlarge
   Coastal habitat near the vicinity of Vicente Creek, Moss Beach

   Hickman's potentilla is currently known to occur in three coastal
   locations. The Federal Register documents colonies on the Monterey
   Peninsula and at one site in San Mateo County and it is also known to
   occur on one site in northern Sonoma County. The Monterey population is
   within the municipal boundaries of the city of Monterey growing in fine
   sandy soils within an opening of pine forest that supports wet
   conditions for a variety of native and nonnative grassland species. The
   Monterey County population within the Del Monte Forest is the original
   discovery colony and numbers approximately 2000 plants.

   A second coastal colony was discovered in Moss Beach, California in
   1933 in a wetland area at the mouth of San Vicente Creek; this colony
   was presumed extirpated by at least the 1970s. Another population in
   San Mateo County was discovered in 1995 on the south slopes above
   Martini Creek ( USGS quad reference Montara Mountain 3712254), on
   private land by biologists conducting surveys for the Devil's Slide
   highway project. The Sonoma County population is situated in the
   Stemple Creek coastal watershed and is within USGS quad reference Two
   Rock 3812237. In all cases the populations are found between altitude
   10 to 135 meters. The habitat for this species includes vernally wet
   meadows or open pine forests.

History

   A point on the Monterey Peninsula, that Viscaino mapped
   Enlarge
   A point on the Monterey Peninsula, that Viscaino mapped

   The Monterey Peninsula, discovery site of Hickman's potentilla, is
   recognized to have a high degree of species endemicism. Species with
   more northern ranges often reach their southern limits on the
   Peninsula; species with more southern affinities reach their northern
   limits there as well. The Monterey Peninsula is influenced by a marine
   climate that is pronounced due to the upwelling of cool water from the
   Monterey submarine canyon. Rainfall is 40 to 50 centimeters per year,
   but summer fog-drip is a primary source of moisture for plants that
   would otherwise not be able to persist with such low precipitation.
   Some taxa, such as the coastal closed- cone pines and cypresses are
   relict stands, e.g. species that once extended more widely in the mesic
   climate of the late Pleistocene period, but then retreated to small
   pockets of cooler and wetter conditions along the coast ranges during
   the hotter, drier early Holocene period between 6000 and 2000 BC}.

   The first recorded history of the discovery site was in 1602, by the
   Spanish explorer Sebastian Viscaino, whose mission was mapping of the
   coastline. Viscaino noted in his journal the presence of "pine covered
   headlands...great pine trees, smooth and straight".

   Alice Eastwood discovered P. hickmansii in the year 1900 on the
   Monterey Peninsula, a region then considered the fringe of
   civilization. The Big Sur wilderness lay just beyond, unpenetrated by
   any roads at that time. Eastwood, Curator of Botany at the California
   Academy of Sciences in San Francisco was a pioneer biologist in
   exploring this remote area. On an expedition to amass specimens of rare
   plants from this southern reach of Monterey County, she retrieved a
   specimen of this previously unrecorded plant and named this species
   after J. B. Hickman, her guide on that collecting trip. Eastwood's
   commitment to her work was demonstrated in the aftermath of the 1906
   San Francisco earthquake. She rushed to the heavily damaged California
   Academy of Sciences building on Market Street, and climbed metal
   railings of collapsed staircases to reach the herbarium on the sixth
   floor, while the building was burning. She succeeded in saving nearly
   1500 specimens, including the entire type specimen collection, before
   the remainder of the largest botanical collection in the western United
   States was consumed in the resulting fire.

Conservation status

   In the year 1973 the state of California recognized Hickman's
   potentilla as an endangered species. In the early to mid 1990s a series
   of steps occurred that led to federal classification as an endangered
   species. Certain land development proposals came before the city of
   Monterey related to pine forest habitat area. In preparing an
   Environmental Impact Report, information on occurrences of Hickman’s
   potentilla was published. Subsequently in 1995 the U.S. Environmental
   Protection Agency (EPA) acted on this new information regarding a
   species that some thought extinct, and promulgated a notice of intent
   to classify the species as endangered.

   In 1998 the United States Congress officially classified Hickman's
   potentilla as endangered. After the EPA nomination process, further
   colonies in San Mateo and Sonoma Counties became defined. This chain of
   events illustrates the role of the Environmental Impact Statement in
   elucidating scientific information germane to the understanding of an
   entire species, beyond the intended role of analyzing effects on the
   physical environment of a specific project.

   P. Hickmanii continues to be pressured by urban development, especially
   on the Monterey Peninsula with chief elements of golf courses and
   housing to support the expanding human population. These pressures are
   partially mitigated by species protection and recovery plans, the
   latter of which is recognized by the county, local cities, Association
   of Monterey Bay Area Governments and the State of California. The
   federal Recovery Plan (internationally called Biodiversity Action Plan)
   is general in nature, calling for more natural history study,
   population surveys, generalized protection and a vague reference to new
   plantings. Ironically one of the best efforts to enhance the species
   may come from a program that is seemingly unaware of the species. The
   Fitzgerald Marine Reserve Master Plan calls for natural vegetative
   enhancement of Vicente Creek (exact location of the 1933 colony),
   including removal of fill and debris from the creek and extirpation of
   invasive plants. A chief rationale for this plan is protection of the
   California red-legged frog, also an endangered species.

   As a further measure of protection, Monterey County, California has
   explicitly included Hickman's potentilla as a species to be protected
   via its Local Coastal Program pursuant to state of California
   requirements. While the species is listed as federally and state
   endangered, The California Native Plant Society has set the further
   designation of "seriously endangered". This appellation is provided to
   any plant that has fewer than six occurrences, exists on less than 2000
   acres (8 km²) of land area or has fewer than 1000 known organisms.
   Hickman's potentilla satisfies the first criterion.

   Retrieved from " http://en.wikipedia.org/wiki/Hickman%27s_potentilla"
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   with only minor checks and changes (see www.wikipedia.org for details
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