A perennial plant or perennial is a plant that lives more than two years. Some sources cite perennial plants being plants; the term is used to differentiate a plant from shorter-lived annuals and biennials. The term is widely used to distinguish plants with little or no woody growth from trees and shrubs, which are technically perennials. Perennials small flowering plants, that grow and bloom over the spring and summer, die back every autumn and winter, return in the spring from their rootstock, are known as herbaceous perennials. However, depending on the rigors of local climate, a plant, a perennial in its native habitat, or in a milder garden, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings or from divisions. Tomato vines, for example, live several years in their natural tropical/subtropical habitat but are grown as annuals in temperate regions because they don't survive the winter. There is a class of evergreen, or non-herbaceous, including plants like Bergenia which retain a mantle of leaves throughout the year.
An intermediate class of plants is known as subshrubs, which retain a vestigial woody structure in winter, e.g. Penstemon; the local climate may dictate whether plants are treated as perennials. For instance, many varieties of Fuchsia are shrubs in warm regions, but in colder temperate climates may be cut to the ground every year as a result of winter frosts; the symbol for a perennial plant, based on Species Plantarum by Linnaeus, is, the astronomical symbol for the planet Jupiter. Perennial plants can be short-lived or they can be long-lived, as are some woody plants like trees, they include a wide assortment of plant groups from ferns and liverworts to the diverse flowering plants like orchids and grasses. Plants that flower and fruit only once and die are termed monocarpic or semelparous. However, most perennials are polycarpic. Perennials grow structures that allow them to adapt to living from one year to the next through a form of vegetative reproduction rather than seeding; these structures include bulbs, woody crowns, rhizomes plus others.
They might have specialized stems or crowns that allow them to survive periods of dormancy over cold or dry seasons during the year. Annuals produce seeds to continue the species as a new generation while the growing season is suitable, the seeds survive over the cold or dry period to begin growth when the conditions are again suitable. Many perennials have developed specialized features that allow them to survive extreme climatic and environmental conditions; some have adapted to survive cold temperatures. Those plants tend to invest a lot of resource into their adaptations and do not flower and set seed until after a few years of growth. Many perennials produce large seeds, which can have an advantage, with larger seedlings produced after germination that can better compete with other plants; some annuals produce many more seeds per plant in one season, while some perennials are not under the same pressure to produce large numbers of seeds but can produce seeds over many years. Dividing perennial plants is something that gardeners do around the months of October.
The point of doing the division at this time is to allow 6 weeks for adequate root growth prior to the ground reaching a freezing temperature. Due to the leaves falling from trees, as well as the excessive amount of rain received in most places during the fall weeks, the ground has adequate moisture for rapid growth; each type of plant must be separated differently. However, plants such as Irises have a root system known as a Rhizomes, these root systems should be planted with the bulb of the plant just above ground level, with leaves from the following year showing; the point of dividing perennials is to increase the amount of a single breed of plant in your garden. The more you divide your perennial plants every year, the more vast your garden will grow. In warmer and more favorable climates, perennials grow continuously. In seasonal climates, their growth is limited to the growing season. In some species, perennials retain their foliage all year round. Other plants are deciduous perennials, for example, in temperate regions a perennial plant may grow and bloom during the warm part of the year, with the foliage dying back in the winter.
In many parts of the world, seasonality is expressed as wet and dry periods rather than warm and cold periods, deciduous perennials lose their leaves in the dry season. With their roots protected below ground in the soil layer, perennial plants are notably tolerant of wildfire. Herbaceous perennials are able to tolerate the extremes of cold in temperate and Arctic winters, with less sensitivity than trees or shrubs. Perennial plants can be differentiated from annuals and biennials in that perennials have the ability to remain dormant over long periods of time and continue growth and reproduction; the meristem of perennial plants communicates with the hormones produced due to environmental situations and stage of development to begin and halt the ability to grow or flower. There is a distinction between the ability to grow and actual task of growth. For example, most trees regain the ability to grow in the midst of winter but do not initiate physical growth until the spring and summer months.
The start of dormancy can be seen in perennials pla
California is a state in the Pacific Region of the United States. With 39.6 million residents, California is the most populous U. S. the third-largest by area. The state capital is Sacramento; the Greater Los Angeles Area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions, with 18.7 million and 9.7 million residents respectively. Los Angeles is California's most populous city, the country's second most populous, after New York City. California has the nation's most populous county, Los Angeles County, its largest county by area, San Bernardino County; the City and County of San Francisco is both the country's second-most densely populated major city after New York City and the fifth-most densely populated county, behind only four of the five New York City boroughs. California's $3.0 trillion economy is larger than that of any other state, larger than those of Texas and Florida combined, the largest sub-national economy in the world. If it were a country, California would be the 5th largest economy in the world, the 36th most populous as of 2017.
The Greater Los Angeles Area and the San Francisco Bay Area are the nation's second- and third-largest urban economies, after the New York metropolitan area. The San Francisco Bay Area PSA had the nation's highest GDP per capita in 2017 among large PSAs, is home to three of the world's ten largest companies by market capitalization and four of the world's ten richest people. California is considered a global trendsetter in popular culture, innovation and politics, it is considered the origin of the American film industry, the hippie counterculture, fast food, the Internet, the personal computer, among others. The San Francisco Bay Area and the Greater Los Angeles Area are seen as global centers of the technology and entertainment industries, respectively. California has a diverse economy: 58% of the state's economy is centered on finance, real estate services and professional, scientific and technical business services. Although it accounts for only 1.5% of the state's economy, California's agriculture industry has the highest output of any U.
S. state. California is bordered by Oregon to the north and Arizona to the east, the Mexican state of Baja California to the south; the state's diverse geography ranges from the Pacific Coast in the west to the Sierra Nevada mountain range in the east, from the redwood–Douglas fir forests in the northwest to the Mojave Desert in the southeast. The Central Valley, a major agricultural area, dominates the state's center. Although California is well-known for its warm Mediterranean climate, the large size of the state results in climates that vary from moist temperate rainforest in the north to arid desert in the interior, as well as snowy alpine in the mountains. Over time and wildfires have become more pervasive features. What is now California was first settled by various Native Californian tribes before being explored by a number of European expeditions during the 16th and 17th centuries; the Spanish Empire claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its successful war for independence but was ceded to the United States in 1848 after the Mexican–American War.
The western portion of Alta California was organized and admitted as the 31st state on September 9, 1850. The California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom; the word California referred to the Baja California Peninsula of Mexico. The name derived from the mythical island California in the fictional story of Queen Calafia, as recorded in a 1510 work The Adventures of Esplandián by Garci Rodríguez de Montalvo; this work was the fifth in a popular Spanish chivalric romance series that began with Amadis de Gaula. Queen Calafia's kingdom was said to be a remote land rich in gold and pearls, inhabited by beautiful black women who wore gold armor and lived like Amazons, as well as griffins and other strange beasts. In the fictional paradise, the ruler Queen Calafia fought alongside Muslims and her name may have been chosen to echo the title of a Muslim leader, the Caliph. It's possible.
Know ye that at the right hand of the Indies there is an island called California close to that part of the Terrestrial Paradise, inhabited by black women without a single man among them, they lived in the manner of Amazons. They were robust of body with great virtue; the island itself is one of the wildest in the world on account of the craggy rocks. Shortened forms of the state's name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. Various estimates of the native population range from 100,000 to 300,000; the Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups were diverse in their political organization with bands, villages, on the resource-rich coasts, large chiefdoms, such as the Chumash and Salinan.
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Abronia umbellata is a flowering annual plant, native to western North America. Other common names include purple sand verbena; this plant is found in sandy, well-drained soil in areas with low precipitation, it can become a striking carpet-like groundcover in undisturbed areas after winter rains. Pink sand verbena tolerates seaside conditions and is found on the west coast of the North America from British Columbia, Canada to Baja California, Mexico. Sand verbena is found on beaches and sand dunes, below the coastal sage scrub, blooming throughout most of the year. Abronia umbellata is a prostrate annual with thick, succulent leaves and pink to purple colored flowers with white centers. Flowers occur in clusters subtended by 5-8 lanceolate bracts; the flowers do not have petals. The limbs of the perianth is bright colored sometimes to purplish magenta and the tube can be green or red but always-glandular pubescent; the tube includes three stamens. A. Umbellata hybridizes with other species of Abronia, including A. maritima.
Its flower attracts moths. The foliage can be deciduous based on environmental stress; this plant is sometimes used in California in native plant gardening. Described in 1793 by the French botanist Jean-Baptiste Lamarck, Abronia umbellata was collected in 1786 from Monterey, California by the gardener Jean Nicolas Collignon of the French La Pérouse expedition, which had stopped at the capital of Alta California as part of a journey of scientific exploration spanning the Pacific Ocean. While Collignon and his shipmates perished in a wreck near Vanikoro in the Solomon Islands, some of his collection had been shipped back to France during a stop at the Portuguese-held Macao, including the seeds of A. umbellata. They were planted at the Jardin des Plantes in Paris, Lamarck named their descendants A. umbellata, making this species the first Californian flower that does not occur outside of western North America, described in the scientific fashion of Linnaeus. Jepson Manual treatment — Ambronia umbellata United States Department of Agriculture Plants Profile: Abronia umbellata Abronia umbellata — Calphotos Photo Gallery, University of California Las Pilates Nursery: Abronia umbellata Lady Bird Johnson Wildflower Center, University of Texas at Austin: Abronia umbellata
Caryophyllales is an order of flowering plants that includes the cacti, amaranths, ice plants and many carnivorous plants. Many members are succulent, having fleshy leaves; the members of Caryophyllales include about 6% of eudicot species. This order is part of the core eudicots; the Caryophyllales contains 33 families, 692 genera and 11,155 species. The monophyly of the Caryophyllales has been supported by DNA sequences, cytochrome c sequence data and heritable characters such as anther wall development and vessel-elements with simple perforations; as with all taxa, the circumscription of Caryophyllales has changed within various classification systems. All systems recognize a core of families with centrospermous seeds. More recent treatments have expanded the Caryophyllales to include many carnivorous plants. Although the monophyly of the order has been supported, their placement is still uncertain. Systematists are undecided on whether Caryophyllales should be placed within the rosid complex or sister to the asterid clade.
The possible connection between sympetalous angiosperms and Caryophyllales was presaged by Bessey and others. This primitive flower might well be found in centrospermal stock as Wernham and Hutchinson have suggested.' "Caryophyllales is separated into two suborders: Polygonineae. These two suborders were recognized as two orders and Caryophyllales. Kewaceae, Macarthuriaceae and Petiveriaceae were added in APG IV; as circumscribed by the APG III system, this order includes the same families as the APG II system plus the new families, Lophiocarpaceae, Montiaceae and Anacampserotaceae. Family Achatocarpaceae family Aizoaceae family Amaranthaceae family Anacampserotaceae family Ancistrocladaceae family Asteropeiaceae family Barbeuiaceae family Basellaceae family Cactaceae family Caryophyllaceae family Didiereaceae family Dioncophyllaceae family Droseraceae family Drosophyllaceae family Frankeniaceae family Gisekiaceae family Halophytaceae family Kewaceae family Limeaceae family Lophiocarpaceae family Macarthuriaceae family Microteaceae family Molluginaceae family Montiaceae family Nepenthaceae family Nyctaginaceae family Petiveriaceae family Physenaceae family Phytolaccaceae family Plumbaginaceae family Polygonaceae family Portulacaceae family Rhabdodendraceae family Sarcobataceae family Simmondsiaceae family Stegnospermataceae family Talinaceae family Tamaricaceae As circumscribed by the APG II system, this order includes well-known plants like cacti, spinach, rhubarb, venus fly traps, bougainvillea.
Recent molecular and biochemical evidence has resolved additional well-supported clades within the Caryophyllales. Order Caryophyllales family Achatocarpaceae family Aizoaceae family Amaranthaceae family Anacampserotaceae family Ancistrocladaceae family Asteropeiaceae family Barbeuiaceae family Basellaceae family Cactaceae family Caryophyllaceae family Didiereaceae family Dioncophyllaceae family Droseraceae family Drosophyllaceae family Frankeniaceae family Gisekiaceae family Halophytaceae family Limeaceae family Lophiocarpaceae family Molluginaceae family Montiaceae family Nepenthaceae family Nyctaginaceae family Physenaceae family Phytolaccaceae family Plumbaginaceae family Polygonaceae family Portulacaceae family Rhabdodendraceae family Sarcobataceae family Simmondsiaceae family Stegnospermataceae family Talinaceae family Tamaricaceae This represents a slight change from the APG system, of 1998 order Caryophyllales family Achatocarpaceae family Aizoaceae family Amaranthaceae family Ancistrocladaceae family Asteropeiaceae family Basellaceae family Cactaceae family Caryophyllaceae family Didiereaceae family Dioncophyllaceae family Droseraceae family Drosophyllaceae family Frankeniaceae family Molluginaceae family Nepenthaceae family Nyctaginaceae family Physenaceae family Phytolaccaceae family Plumbaginaceae family Polygonaceae family Portulacaceae family Rhabdodendraceae family Sarcobataceae family Simmondsiaceae family Stegnospermataceae family Tamaricaceae The Cronquist system recognised the order, with this circumscription: order Caryophyllales family Achatocarpaceae family Aizoaceae family Amaranthaceae family Basellaceae family Cactaceae family Caryophyllaceae family Chenopodiaceae family Didiereaceae family Nyctaginaceae family Phytolaccaceae family Portulacaceae family MolluginaceaeThe difference with the order as recognized by APG lies in the first place in the concept of "order".
The APG favours much larger orders and families, the order Caryophyllales sensu APG should rather be compared to subclass Caryophyllidae sensu Cronquist. A part of the difference lies with; the plants in the Stegnospermataceae and Barbeuiaceae were included in Cronquist's Phytolaccaceae. The Chenopodiaceae are included in Amaranthaceae by APG. New to the order are the Asteropeiaceae and Physenaceae, each containing a single genus, two genera from Cronquist's order Nepenthales. Earlier systems, such as the Wettstein system, last edition in 1935, the Engler system
Yellowstone National Park
Yellowstone National Park is an American national park located in Wyoming and Idaho. It was established by the U. S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone was the first national park in the U. S. and is widely held to be the first national park in the world. The park is known for its wildlife and its many geothermal features Old Faithful geyser, one of its most popular features, it has many types of ecosystems. It is part of the South Central Rockies forests ecoregion. Native Americans have lived in the Yellowstone region for at least 11,000 years. Aside from visits by mountain men during the early-to-mid-19th century, organized exploration did not begin until the late 1860s. Management and control of the park fell under the jurisdiction of the Secretary of the Interior, the first being Columbus Delano. However, the U. S. Army was subsequently commissioned to oversee management of Yellowstone for a 30-year period between 1886 and 1916. In 1917, administration of the park was transferred to the National Park Service, created the previous year.
Hundreds of structures have been built and are protected for their architectural and historical significance, researchers have examined more than a thousand archaeological sites. Yellowstone National Park spans an area of 3,468.4 square miles, comprising lakes, canyons and mountain ranges. Yellowstone Lake is one of the largest high-elevation lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent; the caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geysers and hydrothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone; the park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly-intact ecosystem in the Earth's northern temperate zone. In 1978, Yellowstone was named a UNESCO World Heritage Site. Hundreds of species of mammals, birds and reptiles have been documented, including several that are either endangered or threatened.
The vast forests and grasslands include unique species of plants. Yellowstone Park is the largest and most famous megafauna location in the contiguous United States. Grizzly bears and free-ranging herds of bison and elk live in this park; the Yellowstone Park bison herd is the largest public bison herd in the United States. Forest fires occur in the park each year. Yellowstone has numerous recreational opportunities, including hiking, boating and sightseeing. Paved roads provide close access to the major geothermal areas as well as some of the lakes and waterfalls. During the winter, visitors access the park by way of guided tours that use either snow coaches or snowmobiles; the park contains the headwaters of the Yellowstone River. Near the end of the 18th century, French trappers named the river Roche Jaune, a translation of the Hidatsa name Mi tsi a-da-zi. American trappers rendered the French name in English as "Yellow Stone". Although it is believed that the river was named for the yellow rocks seen in the Grand Canyon of the Yellowstone, the Native American name source is unclear.
The human history of the park begins at least 11,000 years ago when Native Americans began to hunt and fish in the region. During the construction of the post office in Gardiner, Montana, in the 1950s, an obsidian projectile point of Clovis origin was found that dated from 11,000 years ago; these Paleo-Indians, of the Clovis culture, used the significant amounts of obsidian found in the park to make cutting tools and weapons. Arrowheads made of Yellowstone obsidian have been found as far away as the Mississippi Valley, indicating that a regular obsidian trade existed between local tribes and tribes farther east. By the time white explorers first entered the region during the Lewis and Clark Expedition in 1805, they encountered the Nez Perce and Shoshone tribes. While passing through present day Montana, the expedition members heard of the Yellowstone region to the south, but they did not investigate it. In 1806, John Colter, a member of the Lewis and Clark Expedition, left to join a group of fur trappers.
After splitting up with the other trappers in 1807, Colter passed through a portion of what became the park, during the winter of 1807–1808. He observed at least one geothermal area near Tower Fall. After surviving wounds he suffered in a battle with members of the Crow and Blackfoot tribes in 1809, Colter described a place of "fire and brimstone" that most people dismissed as delirium. Over the next 40 years, numerous reports from mountain men and trappers told of boiling mud, steaming rivers, petrified trees, yet most of these reports were believed at the time to be myth. After an 1856 exploration, mountain man Jim Bridger reported observing boiling springs, spouting water, a mountain of glass and yellow rock; these reports were ignored because Bridger was a known "spinner of yarns". In 1859, a U. S. Army Surveyor named Captain William F. Raynolds embarked on a two-year survey of the northern Rockies. After wintering in Wyoming, in May 1860, Raynolds and his party – which included naturalist Ferdinand Vandeveer Hayden and guide Jim B
Abronia ameliae known as Amelia's sand verbena or heart’s delight, is a species of flowering plant in the Four O'clock family, endemic to southern Texas in the United States. It inhabits grasslands in the deep sands of the Holocene sand sheet, part of the Tamaulipan mezquital; this species was named for wife of Cyrus Longworth Lundell. Media related to Abronia ameliae at Wikimedia Commons
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more they represent problematic species concepts. For example, the boundaries between related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, in a ring species. Among organisms that reproduce only asexually, the concept of a reproductive species breaks down, each clone is a microspecies. All species are given a two-part name, a "binomial"; the first part of a binomial is the genus.
The second part is called the specific epithet. For example, Boa constrictor is one of four species of the genus Boa. None of these is satisfactory definitions, but scientists and conservationists need a species definition which allows them to work, regardless of the theoretical difficulties. If species were fixed and distinct from one another, there would be no problem, but evolutionary processes cause species to change continually, to grade into one another. Species were seen from the time of Aristotle until the 18th century as fixed kinds that could be arranged in a hierarchy, the great chain of being. In the 19th century, biologists grasped. Charles Darwin's 1859 book The Origin of Species explained how species could arise by natural selection; that understanding was extended in the 20th century through genetics and population ecology. Genetic variability arises from mutations and recombination, while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures.
Genes can sometimes be exchanged between species by horizontal gene transfer. Viruses are a special case, driven by a balance of mutation and selection, can be treated as quasispecies. Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics. Early taxonomists such as Linnaeus had no option but to describe what they saw: this was formalised as the typological or morphological species concept. Ernst Mayr emphasised reproductive isolation, but this, like other species concepts, is hard or impossible to test. Biologists have tried to refine Mayr's definition with the recognition and cohesion concepts, among others. Many of the concepts are quite similar or overlap, so they are not easy to count: the biologist R. L. Mayden recorded about 24 concepts, the philosopher of science John Wilkins counted 26. Wilkins further grouped the species concepts into seven basic kinds of concepts: agamospecies for asexual organisms biospecies for reproductively isolated sexual organisms ecospecies based on ecological niches evolutionary species based on lineage genetic species based on gene pool morphospecies based on form or phenotype and taxonomic species, a species as determined by a taxonomist.
A typological species is a group of organisms in which individuals conform to certain fixed properties, so that pre-literate people recognise the same taxon as do modern taxonomists. The clusters of variations or phenotypes within specimens would differentiate the species; this method was used as a "classical" method of determining species, such as with Linnaeus early in evolutionary theory. However, different phenotypes are not different species. Species named in this manner are called morphospecies. In the 1970s, Robert R. Sokal, Theodore J. Crovello and Peter Sneath proposed a variation on this, a phenetic species, defined as a set of organisms with a similar phenotype to each other, but a different phenotype from other sets of organisms, it differs from the morphological species concept in including a numerical measure of distance or similarity to cluster entities based on multivariate comparisons of a reasonably large number of phenotypic traits. A mate-recognition species is a group of sexually reproducing organisms that recognize one another as potential mates.
Expanding on this to allow for post-mating isolation, a cohesion species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms. A further development of the recognition concept is provided by the biosemiotic concept of species. In microbiology, genes can move even between distantly related bacteria extending to the whole bacterial domain; as a rule of thumb, microbiologists have assumed that kinds of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA-DNA hybridisation to decide if they belong to the same species or not. This concept was narrowed in 2006 to a similarity of 98.7%. DNA-DNA hybri