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Dichanthelium Leibergii
''Dichanthelium leibergii'', known as variously as Leiberg's panicum, Leiberg's panicgrass, Leiberg's rosette grass, and prairie panic grass is a species of grass native to North America. It was named for its discoverer, John Bernhard Leiberg (1853-1913), a Swedish-born American botanist active in the western United States. Description Leiberg's panicgrass is a small perennial grass forming loose rosettes with culms between in height. It is distinguished from other similar species of ''Dichanthelium'' by a combination of the following characters: * leave less than wide and less than 15-20 times as long as wide * leaves hairy * stem slender with narrowly ovoid panicle * spikelets with long, soft hairs up to in length * first glume narrowly ovate, reaching the middle of the spikelet Distribution ''Dichanthelium leibergii'' ranges north to Alberta, west to Kansas, and east to New York state. Although it is "fairly common" in Manitoba, it is a rare species across much of its ran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Velutina
''Quercus velutina'' (Latin 'velutina', "velvety") , the black oak, is a species of oak in the red oak group (''Quercus'' sect. ''Lobatae''), native and widespread in eastern and central North America. It is sometimes called the eastern black oak. ''Quercus velutina'' was previously known as yellow oak due to the yellow pigment in its inner bark. It is a close relative of the California black oak (''Quercus kelloggii'') found in western North America. Description In the northern part of its range, ''Quercus velutina'' is a relatively small tree, reaching a height of and a diameter of , but it grows larger in the south and center of its range, where heights of up to are known. The leaves of the black oak are alternately arranged on the twig and are long with 5–7 bristle-tipped lobes separated by deep U-shaped notches. The upper surface of the leaf is a shiny deep green, and the lower is yellowish-brown. There are also stellate hairs on the underside of the leaf that grow in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prairie Restoration
Prairie restoration is a conservation effort to restore prairie lands that were destroyed due to industrial, agricultural, commercial, or residential development. The primary aim is to return areas and ecosystems to their previous state before their depletion. In the United States, after the Black Hawk War had subsided in the mid-1830s, settlers from northern Europe and north east of the US made a home for themselves. They plowed up the tallgrasses and wild flowers in the area. By 1849 most species of prairie grass had disappeared to make room for crops (i.e.: soybeans, corn, etc.). Restored prairies and the grasses that survived the 1800 plowing represent only a fragment of the abundant verdure that once covered the midsection of North America from western Ohio to the Rockies and from southern Canada to Texas. As an example, the U.S. state of Illinois alone once held over 35,000 square miles (91,000 km2) of prairie land and now just 3 square miles (7.8 km2) of that o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invasive Species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food web. Since the 20th century, invasive species have become serious economic, social, and environmental threats worldwide. Invasion of long-established ecosystems by organisms is a natural phenomenon, but human-facilitated introductions have greatly increased the rate, scale, and geographic range of invasion. For millennia, humans have served as both accidental and deliberate dispersal agents, beginning with their earliest migrations, accelerating in the Age of Discovery, and accelerating again with the spread of international trade. Notable invasive plant species include the kudzu vine, giant hogweed (''Heracleum mantegazzianum''), Japanese knotw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat Destruction
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease in biodiversity and species numbers. Habitat destruction is in fact the leading cause of biodiversity loss and species extinction worldwide. Humans contribute to habitat destruction through the use of natural resources, agriculture, industrial production and urbanization (urban sprawl). Other activities include mining, logging and trawling. Environmental factors can contribute to habitat destruction more indirectly. Geological processes, climate change, introduction of invasive species, ecosystem nutrient depletion, water and noise pollution are some examples. Loss of habitat can be preceded by an initial habitat fragmentation. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat Fragmentation
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes that slowly alter the layout of the physical environment (suspected of being one of the major causes of speciation), and human activity such as land conversion, which can alter the environment much faster and causes the extinction of many species. More specifically, habitat fragmentation is a process by which large and contiguous habitats get divided into smaller, isolated patches of habitats. Definition The term habitat fragmentation includes five discrete phenomena: * Reduction in the total area of the habitat * Decrease of the interior: edge ratio * Isolation of one habitat fragment from other areas of habitat * Breaking up of one patch of habitat into several smaller patches * Decrease in the average size of each patch of habit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prescribed Burning
A controlled burn or prescribed burn (Rx burn) is the practice of intentionally setting a fire to change the assemblage of vegetation and decaying material in a landscape. The purpose could be for forest management, ecological restoration, land clearing or wildfire fuel management. Controlled burns may also be referred to as hazard reduction burning'', ''backfire'', ''swailing or a burn-off. Controlled burns are conducted during the cooler months to reduce fuel buildup and decrease the likelihood of more dangerous, hotter fires. Controlled burning stimulates the germination of some trees and reveals soil mineral layers which increases seedling vitality. In grasslands, controlled burns shift the species assemblage to primarily native grassland species. Some seeds, such as those of lodgepole pine, sequoia and many chaparral shrubs are pyriscent, meaning heat from fire causes the cone or woody husk to open and disperse seeds. Fire is a natural part of both forest and grassla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Cover
The abundances of plant species are often measured by plant cover, which is the relative area covered by different plant species in a small plot. Plant cover is not biased by the size and distributions of individuals, and is an important and often measured characteristic of the composition of plant communities. Usage Plant cover data may be used to classify the studied plant community into a vegetation type, to test different ecological hypotheses on plant abundance, and in gradient studies, where the effects of different environmental gradients on the abundance of specific plant species are studied . Measurement The most common way to measure plant cover in herbal plant communities, is to make a visual assessment of the relative area covered by the different species in a small plot (see quadrat). The visually assessed cover of a plant species is then recorded as a continuous variable between 0 and 1, or divided into interval classes as an ordinal variable. An alternative method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prairie Remnant
A prairie remnant commonly refers to grassland areas in the Western and Midwestern United States and Canada that remain to some extent undisturbed by European settlement. Prairie remnants range in levels of degradation, but nearly all contain at least some semblance of the pre-Columbian local plant assemblage of a particular region. Prairie remnants have become increasingly threatened due to the threats of agricultural, urban and suburban development, pollution, fire suppression, and the incursion of invasive species. Prairie remnants in restoration ecology Prairie remnants offer valuable varieties of rare species, thus providing excellent opportunities for restoration ecology projects. Many restoration projects are simply recreations of prairie habitats, but restoring prairie remnants preserves more complete ecological structures that were naturally created after the end of the last ice age. Remnants can also be platforms for additional surrounding ecological restoration activi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Vasey (botanist)
George Vasey (February 28, 1822 – March 4, 1893) was an English-born American physician, botanist, and agrostologist. He practiced medicine in Illinois for nearly two decades before being appointed Chief Botanist at the United States Department of Agriculture in 1872, a position he held for the remainder of his life. In 1889 the Smithsonian Institution named him Honorary Curator of the United States National Herbarium, the crowning achievement of his career. The alias George S. Vasey is often used to avoid confusion with his son George Richard Vasey. However, the father never used a middle initial in the 19th century. On letters and publications, he signed his name as George Vasey, , or . Most of his herbarium specimens are labeled with the name or one of the previous names. The source of the middle initial is unknown. Life George Vasey was born on February 28, 1822 near the town of Scarborough, England, the fourth of ten children. His family emigrated to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coefficient Of Conservatism
Floristic Quality Assessment (FQA) is a tool used in the United States to assess an area's ecological integrity based on its plant species composition. Floristic Quality Assessment was originally developed in order to assess the likelihood that impacts to an area "would be irreversible or irretrievable...to make standard comparisons among various open land areas, to set conservation priorities, and to monitor site management or restoration efforts." The concept was developed by Gerould Wilhelm in the 1970s in a report on the natural lands of Kane County, Illinois. In 1979 Wilhelm and Floyd Swink codified this "scoring system" for the 22-county Chicago Region. Coefficient of conservatism Each plant species in a region is assigned a coefficient of conservatism, also known as a C-value, ranging between 0 and 10. A plant species with a higher score (e.g. 10) has a ''lower'' tolerance to environmental degradation such as overgrazing or development and therefore is naturally restri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Culm (botany)
A culm is the aerial (above-ground) Plant stem, stem of a Poaceae, grass or Cyperaceae, sedge. It is derived from Latin , meaning "stalk." It originally referred to the stem of any type of plant. In horticulture or agriculture, it is especially used to describe the stalk or woody stems of bamboo, cane (grass), cane or cereal, grain grasses. Malting In the production of malted grains, the culms refer to the rootlets of the germinated grains. The culms are normally removed in a process known as "deculming" after kilning when producing barley malt, but form an important part of the product when making sorghum or millet malt. These culms are very nutritious and are sold off as animal feed. References Plant morphology {{Plant-morphology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
