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Notholithocarpus
''Notholithocarpus densiflorus'', commonly known as the tanoak or tanbark-oak, is a broadleaf tree in the family Fagaceae, and the type species of the genus ''Notholithocarpus''. It is a hardwood tree that is native to the far western United States, particularly Oregon and California. It ranges from in height, with a trunk diameter of . There are a number of radical and incompatible perceptions of tanoak, it has been seen as a cash crop to treasured food plant to trash tree. Description It can reach tall in the California Coast Ranges, though is more usual, and can have a trunk diameter of . The bark is fissured, and ranges from gray to brown. The tree's average age appears to be 180 years, although some estimates reach as high as 300 to 400 years old. The leaves are alternate, , with toothed margins and a hard, leathery texture. At first they are covered in dense orange-brown scurfy hairs on both sides, which wear off over time, more slowly on the underside of the leaf. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithocarpus
''Lithocarpus'' is a genus in the beech family, Fagaceae. Trees in this genus are commonly known as the stone oaks and differ from ''Quercus'' primarily because they produce insect-pollinated flowers on erect spikes and the female flowers have short styles with punctate stigmas. At current, around 340 species have been described, mostly restricted to Southeast Asia. Fossils show that ''Lithocarpus'' formerly had a wider distribution, being found in North America and Europe during the Eocene to Miocene epochs. The species extend from the foothills of the Hengduan Mountains, where they form dominant stands of trees, through Indochina and the Malayan Archipelago, crossing Wallace's Line and reaching Papua. In general, these trees are most dominant in the uplands (more than above sea level) and have many ecological similarities to the Dipterocarpaceae, the dominant lowland tree group. These trees are intolerant of seasonal droughts, not being found on the Lesser Sunda Islands, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fagaceae
The Fagaceae (; ) are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with around 1,000 or more species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergreen trees and shrubs. They are characterized by alternate simple leaves with pinnate venation, unisexual flowers in the form of catkins, and fruit in the form of cup-like (Calybium and cupule, cupule) nuts. Their leaves are often lobed, and both petiole (botany), petioles and stipules are generally present. Their fruits lack endosperm and lie in a scaly or spiny husk that may or may not enclose the entire nut, which may consist of one to seven seeds. In the oaks, genus ''Quercus'', the fruit is a non-valved nut (usually containing one seed) called an acorn. The husk of the acorn in most oaks only forms a cup in which the nut sits. Other members of the family have fully enclosed nuts. Fagaceae is one of the most ecologically i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytophthora Ramorum
''Phytophthora ramorum'' is the oomycete known to cause the disease sudden oak death (SOD). The disease kills oak and other species of trees and has had devastating effects on the oak populations in California and Oregon, as well as being present in Europe. Symptoms include bleeding cankers on the tree's Trunk (botany), trunk and Forest dieback, dieback of the foliage, in many cases leading to the death of the tree. ''P. ramorum'' also infects a great number of other plant species, significantly woody ornamental plant, ornamentals such as ''Rhododendron'', ''Viburnum'', and ''Pieris (plant), Pieris'', causing foliar symptoms known as ramorum dieback or ramorum blight. Such plants can act as a source of Propagule, inoculum for new infections, with the pathogen producing spores that can be transmitted by rainsplash and rainwater. ''P. ramorum'' was first reported in 1995, and the origins of the pathogen are still unclear, but most evidence suggests it was introduced as an exotic sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn
The acorn is the nut (fruit), nut of the oaks and their close relatives (genera ''Quercus'', ''Notholithocarpus'' and ''Lithocarpus'', in the family Fagaceae). It usually contains a seedling surrounded by two cotyledons (seedling leaves), enclosed in a tough Nutshell, shell known as the pericarp, and borne in a cup-shaped Calybium, cupule. Acorns are long and on the fat side. Acorns take between 5 and 24 months (depending on the species) to mature; see the List of Quercus species, list of ''Quercus'' species for details of oak classification, in which acorn morphology (biology), morphology and phenology are important factors. Etymology The word ''acorn'' (earlier ''akerne'', and ''acharn'') is related to the gothic language, Gothic name ''akran'', which had the sense of "fruit of the unenclosed land". The word was applied to the most important forest produce, that of the oak. Geoffrey Chaucer, Chaucer spoke of "achornes of okes" in the 14th century. By degrees, popular etym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sierra Nevada (U
The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley (California), Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada. The Sierra Nevada is part of the American Cordillera, an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas. The Sierra runs north-south, and its width ranges from to across east–west. Notable features include the General Sherman Tree, the largest tree in the world by volume; Lake Tahoe, the largest alpine lake in North America; Mount Whitney at , the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite, containing List of waterfalls in Yosemite National Park, high waterfalls. The Sierra is home to three national parks, twenty-six wilderness areas, ten national forests, and two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disturbance (ecology)
In ecology, a disturbance is a change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic component, biotic and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem. Ecological disturbances include fires, flooding, storms, insect outbreaks, trampling, Human impact on the environment, human presence, earthquakes, plant diseases, infestations, volcanic eruptions, impact events, etc. Not only invasive species can have a profound effect on an ecosystem, native species can also cause disturbance by their behavior. Disturbance forces can have profound immediate effects on ecosystems and can, accordingly, greatly alter the Biocoenosis, natural community’s population size or species richness. Because of these and the impacts on populations, disturbance determines the future shifts i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shade Tolerant
In ecology, shade tolerance is a plant's ability to tolerate low light levels. The term is also used in horticulture and landscaping, although in this context its use is sometimes imprecise, especially in labeling of plants for sale in nursery (horticulture), commercial nurseries. Shade tolerance is a complex, multi-faceted property of plants. Different plant species exhibit different adaptations to shade (shadow), shade, and a particular plant can exhibit varying degrees of shade tolerance, or even of requirement for light, depending on its history or stage of development. Basic concepts Except for some parasitic plants, all land plants need sunlight to survive. However, in general, more sunlight does not always make it easier for plants to survive. In direct sunlight, plants face desiccation and exposure to UV rays, and must expend energy producing pigments to block UV light, and waxy coatings to prevent water loss. Plants adapted to shade have the ability to use far-red light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sierra Nevada
The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada. The Sierra Nevada is part of the American Cordillera, an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas. The Sierra runs north-south, and its width ranges from to across east–west. Notable features include the General Sherman Tree, the largest tree in the world by volume; Lake Tahoe, the largest alpine lake in North America; Mount Whitney at , the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite, containing high waterfalls. The Sierra is home to three national parks, twenty-six wilderness areas, ten national forests, and two national monuments. These areas include Yosemite, Sequoia, and Ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transverse Ranges
The Transverse Ranges are a group of mountain ranges of Southern California, in the Pacific Coast Ranges physiographic region in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie within Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside and Kern counties. The Peninsular Ranges lie to the south. The name is due to the ranges' east–west orientation, making them wikt:transverse, transverse to the general northwest–southeast orientation of most of California's coastal mountains.Dibblee Jr, T.W., 1982. Regional geology of the Transverse Ranges Province of southern California. ''Geology and mineral wealth of the California Transverse Ranges'', ''10'', pp.7-26. The ranges extend from west of Point Conception eastward approximately 500 kilometers into the Mojave Desert, Mojave and Colorado Desert. The geology and topography of the ranges express three distinct segments that have contrasting elevations, rock types, and veg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountaineers Books
The Mountaineers is an alpine club in the US state of Washington. Founded in 1906, it is organized as an outdoor recreation, education, and conservation 501(c)(3) nonprofit organization, and is based in Seattle, Washington. The club hosts a wide range of outdoor activities, primarily alpine mountain climbing and hikes. The club also hosts classes, training courses, and social events. The club runs a publishing business, Mountaineers Books, which has several imprints. Publications include '' Mountaineering: The Freedom of the Hills''. Organization and activities The Mountaineers has 7 branches in Western Washington, 3 mountain lodges, and 2 program centers: one in Magnuson Park in Seattle, and one in Tacoma. All classes and trips are organized. History Originally a Seattle-based part of the Mazamas, a Portland based group founded in 1894, The Mountaineers formed their own branch shortly after the 1906 Mazamas Mount Baker expedition and dubbed themselves "The Mountaine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chestnut
The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. The name also refers to the edible nuts they produce. They are native to temperate regions of the Northern Hemisphere. Description Chestnut trees are of moderate growth rate (for the Chinese chestnut tree) to fast-growing for American and European species. Their mature heights vary from the smallest species of chinkapins, often shrubby,''Chestnuts, Horse-Chestnuts, and Ohio Buckeyes'' . In Yard and Garden Brief, Horticulture department at University of Minnesota. to the giant of past American forests, '' C. dentata'' that could reach . Between these extremes ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is Cladogram#Homoplasies, homoplasy. The recurrent evolution of flight is a classic example, as flying pterygota, insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas ''homology (biology), homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different trai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
