Washingtonia filifera
Encyclopedia
Washingtonia filifera with 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 California Fan Palm , Desert Fan Palm, Cotton palm, and Arizona Fan Palm. It is a palm
Arecaceae
Arecaceae or Palmae , are a family of flowering plants, the only family in the monocot order Arecales. There are roughly 202 currently known genera with around 2600 species, most of which are restricted to tropical, subtropical, and warm temperate climates...

 native to southwestern 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...

 between an elevation range of 100–1200 m (328.1–3,937 ft), at seep
Seep (hydrology)
A Seep is a moist or wet place where water, usually groundwater, reaches the earth's surface from an underground aquifer.-Description:Seeps are usually not of sufficient volume to be flowing beyond their above-ground location. They are part of the limnology-geomorphology system...

s, desert bajada
Bajada
Bajada may refer to:*Bajada a festival common to the Canary islands* Bajada, a compound Alluvial fan* La Bajada, an escarpment of the Caja del Rio, New Mexico, USA* Clint Bajada , Maltese TV and radio personality...

s, and spring
Spring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

s where underground water is continuously available.

Distribution

Washingtonia filifera is the only palm native
Native plant
Native plant is a term to describe plants endemic or naturalized to a given area in geologic time.This includes plants that have developed, occur naturally, or existed for many years in an area...

 to the Western United States
Western United States
.The Western United States, commonly referred to as the American West or simply "the West," traditionally refers to the region comprising the westernmost states of the United States. Because the U.S. expanded westward after its founding, the meaning of the West has evolved over time...

,including Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

, and 'palm iconic' California. It is the largest native palm in the contiguous United States
Contiguous United States
The contiguous United States are the 48 U.S. states on the continent of North America that are south of Canada and north of Mexico, plus the District of Columbia....

. The primary populations are found in desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

 riparian habitats at spring fed oases
Oasis
In geography, an oasis or cienega is an isolated area of vegetation in a desert, typically surrounding a spring or similar water source...

 in the Colorado Desert
Colorado Desert
California's Colorado Desert is a part of the larger Sonoran Desert, which extends across southwest North America. The Colorado Desert region encompasses approximately , reaching from the Mexican border in the south to the higher-elevation Mojave Desert in the north and from the Colorado River in...

 (Low Desert) of Southern California
Southern California
Southern California is a megaregion, or megapolitan area, in the southern area of the U.S. state of California. Large urban areas include Greater Los Angeles and Greater San Diego. The urban area stretches along the coast from Ventura through the Southland and Inland Empire to San Diego...

; with important isolated populations in the Sonoran Desert
Sonoran Desert
The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...

 along the Gila River
Gila River
The Gila River is a tributary of the Colorado River, 650 miles long, in the southwestern states of New Mexico and Arizona.-Description:...

 in Yuma
Yuma County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*70.4% White*2.0% Black*1.6% Native American*1.2% Asian*0.2% Native Hawaiian or Pacific Islander*3.8% Two or more races*20.8% Other races*59.7% Hispanic or Latino -2000:...

 and Yavapai
Yavapai County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*89.3% White*0.6% Black*1.7% Native American*0.8% Asian*0.1% Native Hawaiian or Pacific Islander*2.5% Two or more races*5.0% Other races*13.6% Hispanic or Latino -2000:...

 counties in Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

, and in northern Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...

 of 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...

. It has locally naturalized
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 in the Mojave Desert
Mojave Desert
The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...

 at warm springs near Death Valley
Death Valley
Death Valley is a desert valley located in Eastern California. Situated within the Mojave Desert, it features the lowest, driest, and hottest locations in North America. Badwater, a basin located in Death Valley, is the specific location of the lowest elevation in North America at 282 feet below...

 and southern Clark County, Nevada
Clark County, Nevada
-Demographics:As of the census of 2000, there were 1,375,765 people, 512,253 households, and 339,693 families residing within the MSA. The racial makeup of the MSA was 71.6% White , 9.1% Black, 5.7% Asian, 0.8% American Indian and 12.8% of other or mixed race. 22.0% were Hispanic of any race...

, in extreme northwest Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....

 Mexico, and also in Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

 and the U.S. Virgin Islands. As an ornamental tree it is cultivated in suitable temperate climates worldwide.

Description

The Washingtonia filifera palm grows to 18 metres (59.1 ft) in height (occasionally to 25 metres (82 ft)) in ideal moisture and microclimate conditions. "

The leaf
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....

 frond
Frond
The term frond refers to a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group...

s are up to 6 feet (1.8 m) long, made up of a petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

 up to 2 metres (6.6 ft) long, bearing a fan of leaflets 1.5–2 m (4.9–6.6 ft) long. They have long thread-like white fibers, filifera-fillaments, between the segments. When the fronds die they remain attached and drop down to cloak the trunk in a wide skirt. The shelter that the skirt creates provides a microhabitat for many small birds and invertebrates.

Washingtonia filifera can live from 80 to 250 years or more. The genus name honors George Washington
George Washington
George Washington was the dominant military and political leader of the new United States of America from 1775 to 1799. He led the American victory over Great Britain in the American Revolutionary War as commander-in-chief of the Continental Army from 1775 to 1783, and presided over the writing of...

, the first President of the United States
President of the United States
The President of the United States of America is the head of state and head of government of the United States. The president leads the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces....

. The plant is popularly honored by its common name and habitat used in naming communities and landforms, such as Palm Springs, California
Palm Springs, California
Palm Springs is a desert city in Riverside County, California, within the Coachella Valley. It is located approximately 37 miles east of San Bernardino, 111 miles east of Los Angeles and 136 miles northeast of San Diego...

.

Ecology

Fan palms provide a habitat for Desert Bighorn Sheep
Desert Bighorn Sheep
The Desert Bighorn Sheep is a subspecies of Bighorn Sheep that occurs in the desert Southwest regions of the United States and in the northern regions of Mexico. The trinomial of this species commemorates the American naturalist Edward William Nelson...

 and the California endemic Peninsular Bighorn Sheep
Bighorn Sheep
The bighorn sheep is a species of sheep in North America named for its large horns. These horns can weigh up to , while the sheep themselves weigh up to . Recent genetic testing indicates that there are three distinct subspecies of Ovis canadensis, one of which is endangered: Ovis canadensis sierrae...

, Hooded Oriole
Hooded Oriole
The Hooded Oriole, Icterus cucullatus, is a medium-sized New World oriole.Adults have a pointed bill and white wing bars. The adult male has an orange head with black on the face and throat; they are black on the back, wings and tail, orange on the underparts...

, Gambel's Quail
Gambel's Quail
The Gambel's Quail, Callipepla gambelii, is a small ground-dwelling bird in the New World quail family. It inhabits the desert regions of Arizona, California, Colorado, New Mexico, Nevada, Utah, Texas, and Sonora; also New Mexico-border Chihuahua and the Colorado River region of Baja California...

, Coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s, and a rare bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

 species (Lasiurus xanthinus) that is especially fond of W. filifera groves. Hooded Orioles rely on the trees for food and places to build nests. Both Hooded Orioles and coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s play an integral part in seed distribution.

Access
Joshua Tree National Park
Joshua Tree National Park
Joshua Tree National Park is located in southeastern California. Declared a U.S. National Park in 1994 when the U.S. Congress passed the California Desert Protection Act , it had previously been a U.S. National Monument since 1936. It is named for the Joshua tree forests native to the park...

 preserves and protects healthy riparian palm habitat examples in the Little San Bernardino Mountains
Little San Bernardino Mountains
The Little San Bernardino Mountains are a short mountain range of the Transverse Ranges, located in southern California in the United States. They extend for approximately 40 mi southeast from the San Bernardino Mountains through San Bernardino and Riverside Counties to near the northeast...

 section, and westward where water surfaces up through the San Andreas Fault
San Andreas Fault
The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...

 on the east valley side. In the central Coachella Valley
Coachella Valley
Coachella Valley is a large valley landform in Southern California. The valley extends for approximately 45 miles in Riverside County southeast from the San Bernardino Mountains to the saltwater Salton Sea, the largest lake in California...

 the Indio Hills Palms State Reserve
Indio Hills Palms
Indio Hills Palms State Reserve and the Coachella Valley Preserve, located in the Indio Hills, contain the 1,000 Palms Oasis, and are a protected area in the Coachella Valley, located east of Palm Springs near Palm Desert, California...

 and nearby Coachella Valley Preserve
Coachella Valley National Wildlife Refuge
Coachella Valley National Wildlife Refuge is a protected area in the Coachella Valley, located east of Palm Springs near Palm Desert, California...

 a large oasis is protected and accessible. In the Santa Rosa Mountains
Santa Rosa Mountains
Santa Rosa Mountains may refer to the following mountains in the United States of America:*Santa Rosa Mountains *Santa Rosa Mountains Other similar names include*The Santa Rosa Range in northern Nevada...

 on the west side of the valley, at 'Palm Canyon' in the Santa Rosa and San Jacinto Mountains National Monument
Santa Rosa and San Jacinto Mountains National Monument
The Santa Rosa and San Jacinto Mountains National Monument is a National Monument in Southern California. It includes portions of the Santa Rosa and San Jacinto Mountain ranges, the northernmost ones of the Peninsular Ranges system...

, and in Anza-Borrego Desert State Park
Anza-Borrego Desert State Park
Anza-Borrego Desert State Park is a state park located within the Colorado Desert of Southern California. The park takes its name from 18th century, Spanish explorer Juan Bautista de Anza and borrego, the Spanish word for bighorn sheep...

, both parks have large and diverse Washingtonia filifera canyon oases habitats.

Threats

The palm boring beetle Dinapate wrightii (Bostrichidae
Bostrichidae
The Bostrichidae are a family of beetles with more than 700 described species. They are commonly called auger beetles, false powderpost beetles or horned powderpost beetles. The head of most auger beetles cannot be seen from above, as it is downwardly directed and hidden by the thorax...

) can chew through the trunks of the trees. Eventually a continued infestation of beetles can kill various genera and species of palms, including this one. The recent discovery of the red palm weevil (Rhynchophorus ferrugineus
Rhynchophorus ferrugineus
The red palm weevil, Rhynchophorus ferrugineus, is a species of beetle also known as the Asian palm weevil or sago palm weevil. It is relatively large, between two and five centimeters long; usually a rusty red colour, but many colour variants exist and have been often been named as different...

) in Southern California may pose a threat to many palms, with coastal garden Washingtonia filifera trees already a known host.

Today due to urbanization
Urbanization
Urbanization, urbanisation or urban drift is the physical growth of urban areas as a result of global change. The United Nations projected that half of the world's population would live in urban areas at the end of 2008....

 and ground water depletion, palm oases are retracting and disappearing. Increased agriculture irrigation needs of well water has lowered aquifer
Aquifer
An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...

s which decreases or stops water availability at seeps and springs in palm oases. This creates a threat not only to the only native palm of the western United States, but also all the organisms which rely on the riparian palm oases habitat to survive.

History
Fossils of this palm are known to exist as far north as Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

, Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 and Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

. The palm apparently reached its current form by at least 50 - 70 million years BP.

Natural oases environments are mainly restricted historically to the area surrounding warm or hot springs, near the source, or shortly downstream from the source.

Grazing animals including deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...

 and cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

 and in more ancient times, Giant Sloths and other extinct herbivores, can kill young plants through trampling, or by eating the terminus at the apical meristem, which is the growing portion of the plant. This may have kept these palms restricted to a lesser range than would have been expected if one simply considers the availability of water sources.

Typically, the oasis environment found today is one which may have been protected from colder climatic changes over the course of its evolution. Thus this palm is restricted by both water and climate to widely separated relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....

 groves. The trees in these groves show little if any genetic differentiation, which suggests that this species is genetically very stable.

Native Americans

The fruit of the fan palm was used by Native American
Native Americans in the United States
Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...

s. It was eaten raw, cooked, or ground into flour for cakes. The Cahuilla
Cahuilla
The Cahuilla, Iviatim in their own language, are Indians with a common culture whose ancestors inhabited inland areas of southern California 2,000 years ago. Their original territory included an area of about . The traditional Cahuilla territory was near the geographic center of Southern California...

 tribe used the leaves to make sandals, thatch roofs, and for making baskets. The fan palm was a valuable resource and the stems were used to make utensils for cooking. The Moapa
Moapa
-Places:* Moapa River Indian Reservation, an Indian Reservation in Southern Nevada that is home to some members of the Southern Paiute* Moapa Town, Nevada, a small community of Southern Nevada...

 band of Paiutes as well as other Southern Paiutes have stated memories of grandparents also using this palm's seed, fruit or leaves for various things. The Southern Paiutes are related linguistically and by ancient trade routes to the Cahuilla
Cahuilla
The Cahuilla, Iviatim in their own language, are Indians with a common culture whose ancestors inhabited inland areas of southern California 2,000 years ago. Their original territory included an area of about . The traditional Cahuilla territory was near the geographic center of Southern California...

.

Cultivation

Washingtonia filifera is widely cultivated as an ornamental tree. It is one of the hardiest of Coryphoidiae palms, is tolerant of considerable frost, and is rated as hardy to USDA hardiness zone
Hardiness zone
A hardiness zone is a geographically defined area in which a specific category of plant life is capable of growing, as defined by climatic conditions, including its ability to withstand the minimum temperatures of the zone...

 8. It will survive temperatures of -10 °C with minor damage, and established plants have survived, with severe damage to the foliage, brief periods of temperatures as low as -12 °C. It is a favorite of cold-hardy palm enthusiasts. The plants grow best in warm temperate climate with dry summers and wetter winters. Specimens outside of Mediterranean climates do not grow as large, rarely exceeding 15 metres (49 ft). It is often seen in California with the closely related species Mexican Fan Palm (Washingtonia robusta)
Washingtonia robusta
Washingtonia robusta is a palm tree native to western Sonora and Baja California Sur in northwestern Mexico. It grows to tall, rarely up to . The leaves have a petiole up to long, and a palmate fan of leaflets up to 1 m long. The inflorescence is up to long, with numerous small pale orange-pink...

 - a less hardy palm needing slightly milder winters, that may be visibly damaged at -7 °C and is more amenable to humidity making it more favored along the Gulf Coast.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK