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Tanbark Oak
''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 native to the far western United States, particularly Oregon and California. It ranges from in height, with a trunk diameter of . 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 leaves are alternate, , with toothed margins and a hard, leathery texture, and 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; those on the under surface persist longer but eventually wear off too. The seed is an acorn long and 2 cm in diameter, very similar to an oak acorn, but with a very hard, woody nut shell more like a hazel nut. The nut sits in a cup during its 18-month ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Jackson Hooker
Sir William Jackson Hooker (6 July 178512 August 1865) was an English botanist and botanical illustrator, who became the first director of Kew when in 1841 it was recommended to be placed under state ownership as a botanic garden. At Kew he founded the Herbarium and enlarged the gardens and arboretum. Hooker was born and educated in Norwich. An inheritance gave him the means to travel and to devote himself to the study of natural history, particularly botany. He published his account of an expedition to Iceland in 1809, even though his notes and specimens were destroyed during his voyage home. He married Maria, the eldest daughter of the Norfolk banker Dawson Turner, in 1815, afterwards living in Halesworth for 11 years, where he established a herbarium that became renowned by botanists at the time. He held the post of Regius Professor of Botany at Glasgow University, where he worked with the botanist and lithographer Thomas Hopkirk and enjoyed the supportive friendshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berkeley, California
Berkeley ( ) is a city on the eastern shore of San Francisco Bay in northern Alameda County, California, United States. It is named after the 18th-century Irish bishop and philosopher George Berkeley. It borders the cities of Oakland and Emeryville to the south and the city of Albany and the unincorporated community of Kensington to the north. Its eastern border with Contra Costa County generally follows the ridge of the Berkeley Hills. The 2020 census recorded a population of 124,321. Berkeley is home to the oldest campus in the University of California System, the University of California, Berkeley, and the Lawrence Berkeley National Laboratory, which is managed and operated by the university. It also has the Graduate Theological Union, one of the largest religious studies institutions in the world. Berkeley is considered one of the most socially progressive cities in the United States. History Indigenous history The site of today's City of Berkeley was the territo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytophthora Ramorum
''Phytophthora ramorum'' is the oomycete (a type of protist) plant pathogen 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 and 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 ornamentals such as ''Rhododendron'', ''Viburnum'', and '' Pieris'', causing foliar symptoms known as ramorum dieback or ramorum blight. Such plants can act as a source of 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 species to Europe and North America in se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disturbance (ecology)
In ecology, a disturbance is a temporary 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 and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem. Major ecological disturbances may include fires, flooding, storms, insect outbreaks and trampling. Earthquakes, various types of volcanic eruptions, tsunami, firestorms, impact events, climate change, and the devastating effects of human impact on the environment (anthropogenic disturbances) such as clearcutting, forest clearing and the introduction of invasive species can be considered major disturbances. Not only invasive species can have a profound effect on an ecosystem, but also naturally occurring species can cause disturbance by their behavior. Disturbance forces can have profound immediate effects on ecosystem ... [...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 commercial nurseries. Shade tolerance is a complex, multi-faceted property of plants. Different plant species exhibit different adaptations to 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 (about 730 nm) more effectively ... [...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 General Sherman, 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 wilderness areas, and two national monuments. These areas include Yosemite, Sequoia, and Kings Canyon National Parks; and Devils Po ... [...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 Transverse Ranges is due to their east–west orientation, making them 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 and Colorado Desert. The geology and topography of the ranges express three distinct segments that have contrasting elevations, rock types, and vegetation. The wes ... [...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 organisation, 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 Mountaineers" ... [...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. They are native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce. The unrelated horse chestnuts (genus ''Aesculus'') are not true chestnuts, but are named for producing nuts of similar appearance that are mildly poisonous to humans. True chestnuts should also not be confused with water chestnuts, which are tubers of an aquatic herbaceous plant in the sedge family Cyperaceae. Other species commonly mistaken for chestnut trees are the chestnut oak ('' Quercus prinus'') and the American beech (''Fagus grandifolia''),Chestnut Tree in chestnuttree.net. both of which are also in the Fagaceae family. |
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 homoplasy. The recurrent evolution of flight is a classic example, as flying 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 '' 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 traits. Convergent evolution is similar to parallel evo ... [...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] |
Serpentine Soil
Serpentine soil is an uncommon soil type produced by weathered ultramafic rock such as peridotite and its metamorphic derivatives such as serpentinite. More precisely, serpentine soil contains minerals of the serpentine subgroup, especially antigorite, lizardite, and chrysotile or white asbestos, all of which are commonly found in ultramafic rocks. The term "serpentine" is commonly used to refer to both the soil type and the mineral group which forms its parent materials. Serpentine soils exhibit distinct chemical and physical properties and are generally regarded as poor soils for agriculture. The soil is often reddish, brown, or gray in color due to its high iron and low organic content. Geologically, areas with serpentine bedrock are characteristically steep, rocky, and vulnerable to erosion, which causes many serpentine soils to be rather shallow. The shallow soils and sparse vegetation lead to elevated soil temperatures and dry conditions. Due to their ultramafic origin, ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
