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Toxicodendron Rydbergii
''Toxicodendron rydbergii'', the western poison ivy or northern poison oak, is a species of '' Toxicodendron'' in the cashew family native to North America. As a poison ivy, it can cause urushiol-induced contact dermatitis. Description Unlike ''Toxicodendron radicans'' (eastern poison ivy), which often appears as a trailing or climbing vine, ''T. rydbergii'' is a shrub that can grow to 1 m (3 ft) tall, rarely up to 3 m (10 ft). The leaves are trifoliate and alternate. The leaflets are variable in size and shape, and are usually 15 cm (6 in) long, turning yellow or orange in autumn. On the compound trifoliate leaves, the two leaflets opposite each other are typically asymmetrical, in contrast to the terminal leaflet which always shows bilateral symmetry. The fruits are small, round, and yellowish.
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John Kunkel Small
John Kunkel Small (January 31, 1869 – January 20, 1938) was an American botanist. He studied plants in the southeastern United States and wrote a book about the deterioration of habitats in Florida. Early life and education Small was born on January 31, 1869, in Harrisburg, Pennsylvania, Harrisburg, Pennsylvania. He studied botany at Franklin & Marshall College, receiving his Bachelor's degree in 1892. Then he studied at Columbia University, where he earned a doctorate in philosophy in 1895 and a doctorate in science in 1912. Career After his first graduation in 1895, he became a special agent for the Georgia Geological Survey. Then, returning to Columbia University, he became the first Curator of Museums at the New York Botanical Garden, a post at which he served from 1898 until 1906. It was mainly at that time of his life when he issued several exsiccata, exsiccatae, among others the series ''Mosses of the Southern United States, distributed from the Herbarium of Columb ...
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Urushiol
Urushiol is an oily mixture of organic compounds with Allergic contact dermatitis, allergenic properties found in plants of the Family (biology), family Anacardiaceae, especially ''Toxicodendron'' ''spp.'' (e.g., poison oak, Toxicodendron vernicifluum, Chinese lacquer tree, Toxicodendron radicans, poison ivy, Toxicodendron vernix, poison sumac), Comocladia, ''Comocladia spp.'' (maidenplums), Metopium, ''Metopium spp''. (poisonwood), and also in parts of the Mangifera indica, mango tree and the fruit of the cashew tree. In most individuals, urushiol causes an allergic skin rash on contact, known as urushiol-induced contact dermatitis. The name urushiol is derived from the Japanese language, Japanese word for the lacquer tree, . The oxidation and polymerization of urushiol in the tree's sap in the presence of moisture allows it to form a hard lacquer, which is used to produce traditional Chinese, Korean, and Japanese lacquerware. History Although urushiol-containing lacquers a ...
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Urushiol-induced Contact Dermatitis
Urushiol-induced contact dermatitis (also called Toxicodendron dermatitis or Rhus dermatitis) is a type of allergic contact dermatitis caused by the oil urushiol found in various plants, most notably sumac family species of the genus ''Toxicodendron'': poison ivy, Toxicodendron diversilobum, poison oak, poison sumac, and the Toxicodendron vernicifluum, Chinese lacquer tree. The name is derived from the Japanese word for the sap of the Chinese lacquer tree, ''urushi''. Other plants in the Anacardiaceae, sumac family (including mango, pistachio, the Burmese lacquer tree, the India marking nut tree, and the cashew) also contain urushiol, as do unrelated plants such as ''Ginkgo biloba.'' As is the case with all contact dermatitis, urushiol-induced allergy, allergic rashes are a Type IV hypersensitivity, Type IV hypersensitivity reaction, also known as delayed-type hypersensitivity. Symptoms include itching, inflammation, oozing, and, in severe cases, a burning sensation. The American ...
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River
A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle, the processes by which water moves around the Earth. Water first enters rivers through precipitation, whether from rainfall, the Runoff (hydrology), runoff of water down a slope, the melting of glaciers or snow, or seepage from aquifers beneath the surface of the Earth. Rivers flow in channeled watercourses and merge in confluences to form drainage basins, or catchments, areas where surface water eventually flows to a common outlet. Rivers have a great effect on the landscape around them. They may regularly overflow their Bank (geography), banks and flood the surrounding area, spreading nutrients to the surrounding area. Sedime ...
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Stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. 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 usually called rivers, while smaller, less voluminous and more intermittent river, intermittent streams are known, amongst others, as brook, creek, rivulet, rill, run, tributary, feeder, freshet, narrow river, and streamlet. The flow of a stream is controlled by three inputs – surface runoff (from precipitation or meltwater), daylighting (streams), daylighted subterranean river, subterranean water, and surfaced groundwater (Spring (hydrology), spring water). The surface and subterranean water are highly variable between periods of rainfall. Groundwater, on the other hand, has a relatively constant input and is controlled more by long-term patterns of pr ...
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Forest
A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a Canopy (biology), canopy cover of more than 10 percent, or trees able to reach these thresholds ''in situ''. It does not include land that is predominantly under agricultural or urban use." Using this definition, ''Global Forest Resources Assessment (FRA), Global Forest Resources Assessment 2020'' found that forests covered , or approximately 31 percent of the world's land area in 2020. Forests are the largest Terrestrial ecosystem, terrestrial ecosystems of Earth by area, and are found around the globe. 45 percent of forest land is in the Tropical forest, trop ...
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West Virginia
West Virginia is a mountainous U.S. state, state in the Southern United States, Southern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States.The United States Census Bureau, Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the Bureau of Labor Statistics classifies the state as a part of the Mid-Atlantic (United States), Mid-Atlantic regionMid-Atlantic Home : Mid-Atlantic Information Office: U.S. Bureau of Labor Statistics" www.bls.gov. Archived. It is bordered by Pennsylvania and Maryland to the northeast, Virginia to the southeast, Kentucky to the southwest, and Ohio to the northwest. West Virginia is the List of U.S. states and territories by area, 10th-smallest state by area and ranks as the List of U.S. states and territories by population, 12th-least populous state, with a population of 1,769,979 residents. The capital and List of municipalities in West Virginia, most populou ...
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Extirpated
Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a change in the ecology of an area. It has sometimes been followed by a replacement of the species taken from other locations, such as with wolf reintroduction. Discussion Glaciation is one factor that leads to local extinction. This was the case during the Pleistocene glaciation event in North America. During this period, most of the native North American species of earthworm were killed in places covered by glaciation. This left them open for colonization by European earthworms brought over in soil from Europe. Species naturally become extinct from islands over time; this can be either local extinction if the species also occurs elsewhere, or in cases of island endemism, outright extinction. The number of species an island can support is ...
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California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an international border with the Mexico, Mexican state of Baja California to the south. With almost 40million residents across an area of , it is the List of states and territories of the United States by population, largest state by population and List of U.S. states and territories by area, third-largest by area. Prior to European colonization of the Americas, European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. European exploration in the 16th and 17th centuries led to the colonization by the Spanish Empire. The area became a part of Mexico in 1821, following Mexican War of Independence, its successful war for independence, but Mexican Cession, was ceded to the U ...
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Oregon
Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of its eastern boundary with Idaho. The 42nd parallel north, 42° north parallel delineates the southern boundary with California and Nevada. The western boundary is formed by the Pacific Ocean. Oregon has been home to many Indigenous peoples of the Americas, indigenous nations for thousands of years. The first European traders, explorers, and settlers began exploring what is now Oregon's Pacific coast in the early to mid-16th century. As early as 1564, the Spanish expeditions to the Pacific Northwest, Spanish began sending vessels northeast from the Philippines, riding the Kuroshio Current in a sweeping circular route across the northern part of the Pacific. In 1592, Juan de Fuca undertook detailed mapping a ...
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Nevada
Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, the 32nd-most populous, and the ninth-least densely populated U.S. state. Nearly three-quarters of Nevada's population live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City. Las Vegas is the largest city in the state. Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle Born State" because it achieved statehood during the Civil War (the words "Battle Born" also appear on its state flag); due to the presidency of Abraham Lincoln, the Union benefited immensely from the support of newly awarded statehood by the infusion of t ...
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Southeastern United States
The Southeastern United States, also known as the American Southeast or simply the Southeast, is a geographical List of regions in the United States, region of the United States located in the eastern portion of the Southern United States and the southern portion of the East Coast of the United States, Eastern United States. The region includes a core of states that reaches north to Maryland and West Virginia, bordering the Ohio River and Mason–Dixon line, and stretches west to Arkansas and Louisiana. There is no official Federal government of the United States, U.S. government definition for the region, and it is defined variably among agencies and organizations. History The history of the present-day Southeastern United States dates to the dawn of civilization in approximately 11,000 BC or 13,000 BC. The earliest artifacts from the region were from the Clovis culture. Prior to the arrival of Colonial history of the United States, European colonialists, Native Americans in ...
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