The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
The Pacific Ocean is the largest and deepest of Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by Asia and Australia in the west and the Americas in the east. At 165,250,000 square kilometers in area, this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about one-third of its total surface area, making it larger than all of Earth's land area combined; the centers of both the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean. The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific, its mean depth is 4,000 meters. The Mariana Trench in the western North Pacific is the deepest point in the world, reaching a depth of 10,911 meters; the western Pacific has many peripheral seas. Though the peoples of Asia and Oceania have traveled the Pacific Ocean since prehistoric times, the eastern Pacific was first sighted by Europeans in the early 16th century when Spanish explorer Vasco Núñez de Balboa crossed the Isthmus of Panama in 1513 and discovered the great "southern sea" which he named Mar del Sur.
The ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favorable winds on reaching the ocean. He called it Mar Pacífico, which in both Portuguese and Spanish means "peaceful sea". Important human migrations occurred in the Pacific in prehistoric times. About 3000 BC, the Austronesian peoples on the island of Taiwan mastered the art of long-distance canoe travel and spread themselves and their languages south to the Philippines and maritime Southeast Asia. Long-distance trade developed all along the coast from Mozambique to Japan. Trade, therefore knowledge, extended to the Indonesian islands but not Australia. By at least 878 when there was a significant Islamic settlement in Canton much of this trade was controlled by Arabs or Muslims. In 219 BC Xu Fu sailed out into the Pacific searching for the elixir of immortality. From 1404 to 1433 Zheng He led expeditions into the Indian Ocean; the first contact of European navigators with the western edge of the Pacific Ocean was made by the Portuguese expeditions of António de Abreu and Francisco Serrão, via the Lesser Sunda Islands, to the Maluku Islands, in 1512, with Jorge Álvares's expedition to southern China in 1513, both ordered by Afonso de Albuquerque from Malacca.
The east side of the ocean was discovered by Spanish explorer Vasco Núñez de Balboa in 1513 after his expedition crossed the Isthmus of Panama and reached a new ocean. He named it Mar del Sur because the ocean was to the south of the coast of the isthmus where he first observed the Pacific. In 1519, Portuguese explorer Ferdinand Magellan sailed the Pacific East to West on a Spanish expedition to the Spice Islands that would result in the first world circumnavigation. Magellan called the ocean Pacífico because, after sailing through the stormy seas off Cape Horn, the expedition found calm waters; the ocean was called the Sea of Magellan in his honor until the eighteenth century. Although Magellan himself died in the Philippines in 1521, Spanish Basque navigator Juan Sebastián Elcano led the remains of the expedition back to Spain across the Indian Ocean and round the Cape of Good Hope, completing the first world circumnavigation in a single expedition in 1522. Sailing around and east of the Moluccas, between 1525 and 1527, Portuguese expeditions discovered the Caroline Islands, the Aru Islands, Papua New Guinea.
In 1542–43 the Portuguese reached Japan. In 1564, five Spanish ships carrying 379 explorers crossed the ocean from Mexico led by Miguel López de Legazpi, sailed to the Philippines and Mariana Islands. For the remainder of the 16th century, Spanish influence was paramount, with ships sailing from Mexico and Peru across the Pacific Ocean to the Philippines via Guam, establishing the Spanish East Indies; the Manila galleons operated for two and a half centuries, linking Manila and Acapulco, in one of the longest trade routes in history. Spanish expeditions discovered Tuvalu, the Marquesas, the Cook Islands, the Solomon Islands, the Admiralty Islands in the South Pacific. In the quest for Terra Australis, Spanish explorations in the 17th century, such as the expedition led by the Portuguese navigator Pedro Fernandes de Queirós, discovered the Pitcairn and Vanuatu archipelagos, sailed the Torres Strait between Australia and New Guinea, named after navigator Luís Vaz de Torres. Dutch explorers, sailing around southern Africa engaged in discovery and trade.
In the 16th and 17th centuries Spain considered the Pacific Ocean a mare clausum—a sea closed to other naval powers. As the only known entrance from the Atlantic, the Strait of Magellan was at times patrolled by fleets sent to prevent entrance of non-Spanish ships. On the western side of the Pacific Ocean the Dutch threatened the Spanish Philippines; the 18th cen
Acer negundo is a species of maple native to North America. Box elder, boxelder maple, ash-leaved maple, maple ash are among its common names in the United States. Box elder is a short-lived tree with opposite, compound leaves, it is sometimes considered a invasive species. It has been introduced to and naturalized on most other continents, including in South America, New Zealand, South Africa, much of Europe, parts of Asia. Indicative of its familiarity to many people over a large geographic range, A. negundo has numerous common names. The names "box elder" and "boxelder maple" are based upon the similarity of its whitish wood to that of boxwood and the similarity of its pinnately compound leaves to those of some species of elder; this is the only North American maple with compound leaves, though several Asian species have them. Other common names are based upon this maple's similarity to ash, its preferred environment, its sugary sap, a description of its leaves, its binomial name, so on; these names include three-leaf maple.
In Canada it is known as Manitoba maple and as elf maple. In Russia it is called American maple as well as ash-leaf maple, in Italian acero americano. Common names may designate a particular subspecies. For example, a common name for A. negundo subsp. Interius may be preceded by "inland". A common name for A. negundo subsp. Californicum may be preceded by "California" or "western". Acer negundo is a fast-growing and short-lived tree that grows up to 10–25 m tall, with a trunk diameter of 30–50 cm } up to 1 m } diameter, it has several trunks and can form impenetrable thickets. The shoots are green with a whitish to pink or violet waxy coating when young. Branches are smooth, somewhat brittle, tend to retain a fresh green color rather than forming a bark of dead, protective tissue; the bark on its trunks is pale gray or light brown cleft into broad ridges, scaly. Unlike most other maples, Acer negundo has pinnately compound leaves that have three to seven leaflets. Simple leaves are occasionally present.
Although some other maples have trifoliate leaves, only A. negundo displays more than three leaflets. The leaflets are about 5–10 cm } long and 3–7 cm } wide with serrate margins. Leaves have a translucent light green turn yellow in the fall; the flowers are small and appear in early spring on drooping racemes 10–20 cm } long. The fruits are paired samaras, each seed slender, 1–2 cm } long, with a 2–3 cm } incurved wing. Seeds are both prolific and fertile. Unlike most other maples, A. negundo is dioecious and both a male and female tree are needed for either to reproduce. Winter buds: Terminal buds acute, an eighth of an inch long. Lateral buds obtuse; the inner scales enlarge when spring growth begins and become an inch long before they fall. Flowers: April, before the leaves, yellow green. Pistillate flowers in narrow drooping racemes. Calyx: Yellow green. Pistillate flowers smaller, five-parted. Corolla: Absent. Stamens: Four to six, exserted. Pistil: Ovary hairy, borne on disk enclosed by calyx, two-celled, wing-margined.
Styles separate at base into two stigmatic lobes. Fruit: Maple keys, full size in early summer. Borne in drooping racemes, pedicels one to two inches long. Key an inch and a half to two inches long, nutlets diverging, wings incurved. September. Seed half an inch long. Cotyledons, narrow. Acer negundo is discussed as comprising three subspecies, each of, described as a separate species; these are: A. negundo subsp. Negundo is the main subspecies and the type to which characteristics described in the article most universally apply, its natural range is from the Atlantic Coast to the Rocky Mountains. A. negundo subsp. Interius has more leaf serration than a more matte leaf surface; as the name interus indicates, its natural range of Saskatchewan to New Mexico is sandwiched between that of the other two subspecies. A. negundo subsp. Californicum has larger leaves than the main species. Leaves have a velvety texture, essential to distinguish it from A. negundo subsp. Negundo, it is found in parts of Arizona.
Some authors further subdivide A. negundo subsp. Negundo into a number of regional varieties but these intergrade and their maintenance as distinct taxa is disputed by many; the differences between recognized subspecies are a matter of gradient speciation. A few botanists treat boxelder maple as its own distinct genus but this is not accepted; as noted, varieties thrive across the United States and Canada. It may be found as far south as Guatemala. Although native to North America, it is considered a weedy species in some areas where it is native, such as in the Northeastern United States
The Franciscans are a group of related mendicant religious orders within the Catholic Church, founded in 1209 by Saint Francis of Assisi. These orders include the Order of Friars Minor, the Order of Saint Clare, the Third Order of Saint Francis, they adhere to the teachings and spiritual disciplines of the founder and of his main associates and followers, such as Clare of Assisi, Anthony of Padua, Elizabeth of Hungary, among many others. Francis began preaching around 1207 and traveled to Rome to seek approval from Pope Innocent III in 1209 to form a new religious order; the original Rule of Saint Francis approved by the Pope disallowed ownership of property, requiring members of the order to beg for food while preaching. The austerity was meant to emulate the ministry of Jesus Christ. Franciscans preached in the streets, while boarding in church properties. Saint Clare, under Francis's guidance, founded the Poor Clares in 1212, which remains a Second Order of the Franciscans; the extreme poverty required of members was relaxed in the final revision of the Rule in 1223.
The degree of observance required of members remained a major source of conflict within the order, resulting in numerous secessions. The Order of Friars Minor known as the "Observant" branch, is one of the three Franciscan First Orders within the Catholic Church, the others being the "Conventuals" and "Capuchins"; the Order of Friars Minor, in its current form, is the result of an amalgamation of several smaller orders completed in 1897 by Pope Leo XIII. The latter two, the Capuchin and Conventual, remain distinct religious institutes within the Catholic Church, observing the Rule of Saint Francis with different emphases. Conventual Franciscans are sometimes referred to as greyfriars because of their habit. In Poland and Lithuania they are known as Bernardines, after Bernardino of Siena, although the term elsewhere refers to Cistercians instead; the name of the original order, Ordo Fratrum Minorum stems from Francis of Assisi's rejection of extravagance. Francis was the son of a wealthy cloth merchant, but gave up his wealth to pursue his faith more fully.
He had cut all ties that remained with his family, pursued a life living in solidarity with his fellow brothers in Christ. Francis adopted the simple tunic worn by peasants as the religious habit for his order, had others who wished to join him do the same; those who joined him became the original Order of Friars Minor. The modern organization of the Friars Minor comprises three separate families or groups, each considered a religious order in its own right under its own minister General and particular type of governance, they all live according to a body of regulations known as the Rule of St Francis. First OrderThe First Order or the Order of Friars Minor are called the Franciscans; this order is a mendicant religious order of men, some of whom trace their origin to Francis of Assisi. Their official Latin name is the Ordo Fratrum Minorum. St. Francis thus referred to his followers as "Fraticelli", meaning "Little Brothers". Franciscan brothers are informally called the Minorites; the modern organization of the Friars Minor comprises three separate families or groups, each considered a religious order in its own right under its own minister General and particular type of governance.
They all live according to a body of regulations known as the Rule of St Francis. These are The Order of Friars Minor known as the Observants, are most simply called Franciscan friars, official name: Friars Minor; the Order of Friars Minor Capuchin or Capuchins, official name: Friars Minor Capuchin. The Conventual Franciscans or Minorites, official name: Friars Minor Conventual". Second OrderThe Second Order, most called Poor Clares in English-speaking countries, consists of religious sisters; the order is called the Order of St. Clare, but in the thirteenth century, prior to 1263, this order was referred to as "The Poor Ladies", "The Poor Enclosed Nuns", "The Order of San Damiano". Third OrderThe Franciscan third order, known as the Third Order of Saint Francis, has many men and women members, separated into two main branches: The Secular Franciscan Order, OFS known as the Brothers and Sisters of Penance or Third Order of Penance, try to live the ideals of the movement in their daily lives outside of religious institutes.
The members of the Third Order Regular live in religious communities under the traditional religious vows. They grew out of the Secular Franciscan Order; the 2013 Annuario Pontificio gave the following figures for the membership of the principal male Franciscan orders:. Order of Friars Minor: 2,212 communities. A sermon Francis heard in 1209 on Mt 10:9 made such an impression on him that he decided to devote himself wholly to a life of apostolic poverty. Clad in a rough garment, and, after the Evangelical precept, without staff or scrip, he began to preach repentance, he was soon joined by a prominent fellow townsman, Bernard of Quintavalle, who contributed all that he had to the work, by other companions, who are said to have reached the number of eleven within a yea
Populus trichocarpa, the black cottonwood, western balsam-poplar or California poplar, is a deciduous broadleaf tree species native to western North America. It is used for timber, is notable as a model organism in plant biology. A high-coverage genome sequence was the first tree genome to be sequenced. Assembly of the genome is difficult due to the tetraploidy of the species. However, long-read Pacbio sequencing enabled the assembly of all scaffolds in 2018, it is a large tree, growing to a height of 30 metres to 50 metres and a trunk diameter of over 2 metres, which makes it the largest poplar species in the Americas. It is fairly short-lived, but some trees may live for up to 400 years. A cottonwood in Willamette Mission State Park near Salem, Oregon holds the national and world records. Last measured in April, 2008 this black cottonwood was found to be standing at 155 ft tall, 29 ft around, with 527 points; the bark is grey and covered with lenticels, becoming thick and fissured on old trees.
The bark can become hard enough to cause. The stem is grey in light brown in younger parts; the crown is roughly conical and quite dense. In large trees the lower branches droop downwards. Spur shoots are common; the wood has a straight grain. The leaves are 7–20 cm long with a glossy dark green upper side and glaucous light grey-green underside; the leaves are alternate, elliptic with a crenate margin and an acute tip, reticulate venation. The petiole is reddish; the buds are conical, long and sticky, with a strong balsam scent in spring when they open. Populus trichocarpa has an extensive and aggressive root system, which can invade and damage drainage systems. Sometimes the roots can damage the foundations of buildings by drying out the soil. Flowering and fruiting Populus trichocarpa is dioecious; the species reaches flowering age at about 10 years. Flowers may appear in early March to late May in Washington and Oregon, sometimes as late as mid-June in northern and interior British Columbia and Montana.
Staminate catkins contain 30 to 60 stamens, elongate to 2 to 3 cm, are deciduous. Pistillate catkins at maturity are 8 to 20 cm long with rotund-ovate, three carpellate subsessile fruits 5 to 8 mm long; each capsule contains many minute seeds with white cottony hairs. Seed production and dissemination The seed ripens and is disseminated by late May to late June in Oregon and Washington, but not until mid-July in Idaho and Montana. Abundant seed crops are produced every year. Attached to its cotton, the seed is light and buoyant and can be transported long distances by wind and water. Although viable, longevity of P. trichocarpa seed under natural conditions may be as short as two weeks to a month. This can be increased with cold storage. Seedling development Moist seedbeds are essential for high germination, seedling survival depends on continuously favorable conditions during the first month. Wet bottom lands of rivers and major streams provide such conditions where bare soil has been exposed or new soil laid down.
Germination is epigeal. P. trichocarpa seedlings do not become established in abundance after logging unless special measures are taken to prepare the bare, moist seedbeds required for initial establishment. Where seedlings become established in great numbers, they thin out by age five because the weaker seedlings of this shade-intolerant species are suppressed. Vegetative reproduction Due to its high levels of rooting hormones, P. trichocarpa sprouts readily. After logging operations, it sometimes regenerates from rooting of buried fragments of branches or from stumps. Sprouting from roots occurs; the species has the ability to abscise shoots complete with green leaves. These may root where they fall or may be dispersed by water transport. In some situations, abscission may be one means of colonizing exposed sandbars; the native range of P. trichocarpa covers large sections of western North America. It extends northeast from Kodiak Island along Cook Inlet to latitude 62° 30° N. southeast in southeast Alaska and British Columbia to the forested areas of Washington and Oregon, to the mountains in southern California and northern Baja California.
It is found inland on the west side of the Rocky Mountains, in British Columbia, western Alberta, western Montana, northern Idaho. Scattered small populations have been noted in southeastern Alberta, eastern Montana, western North Dakota, western Wyoming and Nevada, it grows up to elevations of 2100 m. Populus trichocarpa has been one of the most successful introductions of trees to the otherwise treeless Faroe Islands; the species was imported from Alaska to Iceland in 1944 and has since become one of the most widespread trees in the country. It is grown as an ornamental tree, valued for its fast growth and scented foliage in spring, detectable from over 100 m distance; the roots are however invasive, it can damage the foundations of buildings on shrinkable clay soils if planted nearby. Branches can be added to potted plants to stimulate rooting. Populus trichocarpa has several qualities which makes it a good model species for trees: Model genome size Rapid growth Reaches reproductive maturity 4–6 years Economically important It re
Notholithocarpus densiflorus known as the tanoak or tanbark-oak, is an evergreen tree in the family Fagaceae, native to the western United States, in California as far south as the Transverse Ranges, north to southwest Oregon, east in the Sierra Nevada. It can reach 40 m tall in the California Coast Ranges, can have a trunk diameter of 60–190 cm. Tanbark-oak was moved into a new genus, based on multiple lines of evidence, it is most related to the north temperate oaks and not as related to the Asian tropical stone oaks, but instead is an example of convergent morphological evolution. The Notholithocarpus densiflorus leaves are alternate, 7–15 cm, with toothed margins and a hard, leathery texture, persist for three to four years. At first they are covered in dense orange-brown scurfy hairs on both sides, but those on the upper surface soon wear off; the seed is an acorn 2–3 cm long and 2 cm in diameter similar to an oak acorn, but with a hard, woody nut shell more like a hazel nut. The nut sits in a cup during its 18-month maturation.
The nuts are produced in clusters of a few together on a single stem. The nut kernel is bitter, is inedible for people without extensive leaching, although squirrels eat them. Tanoak is one of the species most affected by "sudden oak death", with high mortality reported over much of the species' range. Members of populations in interior California and the Klamath Mountains into southwest Oregon are smaller exceeding 3 m in height and shrubby, with smaller leaves, 4–7 cm long; the variety intergrades with the type in southwest Oregon. Tanoak does grow on serpentine soils as a shrub; some California Native Americans prefer this nut to those of many Quercus acorns because it stores well due to the comparatively high tannin content. The Concow tribe call the nut hä’-hä; the Hupa people use the acorns to make meal, from which they would make mush, biscuits and cakes. They roast the acorns and eat them. Roasted, the seeds can be used as a coffee substitute; the name tanoak refers to its tannin-rich bark, a type of tanbark, used in the past for tanning leather before the use of modern synthetic tannins.
By 1907, the use of tanoak for tannin was subsiding due to the scarcity of large tanoak trees. There weren't enough trees around for a worthwhile economic return. By the early 1960s, there were only a few natural tannin operations left in California; the industry was beginning to switch to a synthetic alternative. A mulch made from the leaves of the plant can repel slugs. Tanoak tannin has been used as an astringent. Tanoak is sometimes used as lumber, but isn't harvested commercially; the largest known tanoak specimen is on private timberland near the town of Ophir, Oregon. It has a circumference of 26 feet, is about 8.25 feet in diameter at breast height, is 121 feet tall with an average crown spread of 56 feet. Media related to Notholithocarpus densiflorus at Wikimedia Commons Jepson Manual treatment Lithocarpus densiflorus in the CalPhotos Photo Database, University of California, Berkeley Interactive Distribution Map of Lithocarpus densiflorus Forest Service Fire Ecology
A stream is a body of water with surface water flowing within the bed and banks of a channel. The stream encompasses surface and groundwater fluxes that respond to geological, geomorphological and biotic controls. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long large streams are called rivers. Streams are important as conduits in the water cycle, instruments in groundwater recharge, corridors for fish and wildlife migration; the biological habitat in the immediate vicinity of a stream is called a riparian zone. Given the status of the ongoing Holocene extinction, streams play an important corridor role in connecting fragmented habitats and thus in conserving biodiversity; the study of streams and waterways in general is known as surface hydrology and is a core element of environmental geography. Brook A stream smaller than a creek one, fed by a spring or seep, it is small and forded. A brook is characterised by its shallowness.
Creek In North America and New Zealand, a small to medium-sized natural stream. Sometimes navigable by motor craft and may be intermittent. In parts of Maryland, New England, the UK and India, a tidal inlet in a salt marsh or mangrove swamp, or between enclosed and drained former salt marshes or swamps. In these cases, the stream is the tidal stream, the course of the seawater through the creek channel at low and high tide. River A large natural stream, which may be a waterway. Runnel the linear channel between the parallel ridges or bars on a shoreline beach or river floodplain, or between a bar and the shore. Called a swale. Tributary A contributory stream, or a stream which does not reach a static body of water such as a lake or ocean, but joins another river. Sometimes called a branch or fork. There are a number of regional names for a stream. Allt is used in Highland Scotland. Beck is used in Lincolnshire to Cumbria in areas which were once occupied by the Danes and Norwegians. Bourne or winterbourne is used in the chalk downland of southern England.
Brook. Burn is used in North East England. Gill or ghyll is seen in Surrey influenced by Old Norse; the variant "ghyll" is used in the Lake District and appears to have been an invention of William Wordsworth. Nant is used in Wales. Rivulet is a term encountered in Victorian era publications. Stream Syke is used in lowland Cumbria for a seasonal stream. Branch is used to name streams in Virginia. Creek is common throughout the United States, as well as Australia. Falls is used to name streams in Maryland, for streams/rivers which have waterfalls on them if such falls have a small vertical drop. Little Gunpowder Falls and The Jones Falls are rivers named in this manner, unique to Maryland. Kill in New York, Pennsylvania and New Jersey comes from a Dutch language word meaning "riverbed" or "water channel", can be used for the UK meaning of'creek'. Run in Ohio, Michigan, New Jersey, Virginia, or West Virginia can be the name of a stream. Run in Florida is the name given to streams coming out of small natural springs.
River is used for larger springs like the Silver Rainbow River. Stream and brook are used in Midwestern states, Mid-Atlantic states, New England. Bar A shoal that develops in a stream as sediment is deposited as the current slows or is impeded by wave action at the confluence. Bifurcation A fork into two or more streams. Channel A depression created by constant erosion. Confluence The point at which the two streams merge. If the two tributaries are of equal size, the confluence may be called a fork. Drainage basin The area of land. A large drainage basin such as the Amazon River contains many smaller drainage basins. Floodplain Lands adjacent to the stream that are subject to flooding when a stream overflows its banks. Gaging station A site along the route of a stream or river, used for reference marking or water monitoring. Headwaters The part of a stream or river proximate to its source; the word is most used in the plural where there is no single point source. Knickpoint The point on a stream's profile where a sudden change in stream gradient occurs.
Mouth The point at which the stream discharges via an estuary or delta, into a static body of water such as a lake or ocean. Pool A segment where the water is deeper and slower moving. Rapids A turbulent, fast-flowing stretch of a stream or river. Riffle A segment where the flow is shallower and more turbulent. River A large natural stream, which may be a waterway. Run A somewhat smoothly flowing segment of the stream. Source The spring, or other point of origin of a stream. Spring The point at which a stream emerges from an underground course through unconsolidated sediments or through caves. A stream can with caves, flow aboveground for part of its course, underground for part of its course. Stream bed The bottom of a stream. Stream corridor Stream, its floodplains, the transitional upland fringe Streamflow The water moving through a stream channel. Thalweg The river's longitudinal section, or the line joining the deepest point in the channel at each stage from source to mouth. Waterfall or cascade The fall of water where the stream goes over a sudden drop called a knickpoint.
The stream expends kinetic energy in "trying" to eliminate the