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California Live Oak
''Quercus agrifolia'', the California live oak, or coast live oak, is a highly variable, often evergreen oak tree, a type of live oak, native to the California Floristic Province. It may be shrubby, depending on age and growing location, but is generally a medium-sized tree. It grows west of the Sierra Nevada mountain range from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section of oaks (''Quercus'' sect. ''Lobatae''). This species is commonly sympatric with canyon live oak (''Q. chrysolepis''), and the two may be hard to distinguish because their spinose leaves are superficially similar. Description Coast live oak typically has a much-branched trunk and reaches a mature height of . Some specimens may attain an age exceeding 1,000 years. Examples of this include the Grand Oak of Cherry Valley, California, the Encino Oak Tree, which died in the 1990s (part of the stump has been preserved) and the Pechanga Grea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luis Née
Luis Née (July 12, 1735 – October 3, 1807) was a French-born Spanish botanist and prolific collector of plant specimens who accompanied the Malaspina Expedition on its five-year scientific exploration of the Pacific Ocean and surrounding lands. In addition to his botanical work he was a pharmacist with a keen interest in medicinal plants and their applications. Early life Little is known about Née's early life. He was born just outside Paris, in Le Perray-en-Yvelines, to a working-class family. He had only a basic education but from an early age exhibited an interest in botany and collecting plants. He eventually moved to Spain and later became a Spanish citizen.JSTOR Global Plants By 1772 Née was working for the pharmacy at the Monastery of Nuestra Señora de la Espina and collecting plants in the mountains of Santander and Asturias. In 1777 he went to work for Casimiro Gómez Ortega, director of the botanic gardens in Madrid, collecting plants and studying in their library ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthetic
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water – hence the name ''photosynthesis'', from the Greek ''phōs'' (), "light", and ''synthesis'' (), "putting together". Most plants, algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies most of the energy necessary for life on Earth. Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centers that contain green chlorophyll (and other colored) pigments/chromophores. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introgression
Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Introgression is a long-term process, even when artificial; it may take many hybrid generations before significant backcrossing occurs. This process is distinct from most forms of gene flow in that it occurs between two populations of different species, rather than two populations of the same species. Introgression also differs from simple hybridization. Simple hybridization results in a relatively even mixture; gene and allele frequencies in the first generation will be a uniform mix of two parental species, such as that observed in mules. Introgression, on the other hand, results in a complex, highly variable mixture of genes, and may only involve a minimal percentage of the donor genome. Definition Introgression or introgressive hybri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shreve Oak
''Quercus parvula'', the Santa Cruz Island oak, is an evergreen red oak (Series ''Agrifoliae'', Section '' Lobatae'') found on north-facing Santa Cruz Island slopes and in the California Coast Ranges from Santa Barbara County north to Mendocino County. It was taxonomically combined with ''Quercus wislizeni'' until resurrected as a separate species by Kevin Nixon in 1980.K. Nixon, "A Systematic Study of ''Quercus parvula'' Greene on Santa Cruz Island and Mainland California," Master's Thesis, 1980. The type locality of ''Q. parvula'' var. ''shrevei'' (originally described by C.H. Muller as ''Q. shrevei'') is Palo Colorado Canyon in Monterey County. Three varieties of ''Q. parvula'' are currently recognized:Jepson Flora Project (eds.) 2015 Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html July 17, 2015 ''Q. parvula'' differs morphologically from its close relative ''Q. wislizeni'' in the following ways: * Leaf blades are larger, > (2)4 cm long rather than < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interior Live Oak
''Quercus wislizeni'', known by the common name interior live oak, is an evergreen oak, highly variable and often shrubby, found in many areas of California in the United States continuing south into northern Baja California in Mexico. It generally occurs in foothills, being most abundant in the lower elevations of the Sierra Nevada, but also widespread in the Pacific Coast Ranges—where since 1980 it has been known as a separate species ''Quercus parvula''—and the San Gabriel Mountains. It was named for its collector, Friedrich Adolph Wislizenus (1810–1889). Description It is a large shrub or tree growing to tall, although where it is common in the low-elevation Sierra Nevada foothills it seldom exceeds . The dark-green leaves—appearing grayish from a distance—are usually small, long, thick, and often spiny-toothed at higher elevations, particularly on young trees. The male flowers are on catkins, the female flowers in leaf axils. The acorns are long, and mature the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomentose
Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant is an indumentum, and the surface bearing them is said to be pubescent. Algal trichomes Certain, usually filamentous, algae have the terminal cell produced into an elongate hair-like structure called a trichome. The same term is applied to such structures in some cyanobacteria, such as '' Spirulina'' and ''Oscillatoria''. The trichomes of cyanobacteria may be unsheathed, as in ''Oscillatoria'', or sheathed, as in ''Calothrix''. These structures play an important role in preventing soil erosion, particularly in cold desert climates. The filamentous sheaths form a persistent sticky network that helps maintain soil structure. Plant trichomes Plant trichomes have many different features that vary between both species of plants and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Wislizeni
''Quercus wislizeni'', known by the common name interior live oak, is an evergreen oak, highly variable and often shrubby, found in many areas of California in the United States continuing south into northern Baja California in Mexico. It generally occurs in foothills, being most abundant in the lower elevations of the Sierra Nevada, but also widespread in the Pacific Coast Ranges—where since 1980 it has been known as a separate species ''Quercus parvula''—and the San Gabriel Mountains. It was named for its collector, Friedrich Adolph Wislizenus (1810–1889). Description It is a large shrub or tree growing to tall, although where it is common in the low-elevation Sierra Nevada foothills it seldom exceeds . The dark-green leaves—appearing grayish from a distance—are usually small, long, thick, and often spiny-toothed at higher elevations, particularly on young trees. The male flowers are on catkins, the female flowers in leaf axils. The acorns are long, and mature the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Kelloggii
''Quercus kelloggii'', the California black oak, also known as Kellogg oak, is an oak in the red oak section (genus ''Quercus'', section ''Lobatae'', series ''Agrifoliae''), native to western North America. Although genetically separated from them for more than 20 million years, its leaves (though not its fruit) are remarkably similar in appearance to several other members of the red oak section including the red oak (''Quercus rubra'') and the black oak (''Quercus velutina'') found in eastern and central North America. Description ''Quercus kelloggii'' typically grows from in height and from in diameter. Large trees may exceed in height and diameter, with the record holder measuring tall and thick (in the Siskiyou National Forest in Oregon). The species also grows in shrubby scrub-oak form on poor sites. In open areas, the crown is broad and rounded, with lower branches nearly touching the ground or forming a browse line. In closed stands, the crown is narrow and slender ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Agrifolia Leaves And Acorn
An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''Lithocarpus'' (stone oaks), as well as in those of unrelated species such as ''Grevillea robusta'' (silky oaks) and the Casuarinaceae (she-oaks). The genus ''Quercus'' is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europe, and North Africa. North America has the largest number of oak species, with approximately 160 species in Mexico of which 109 are endemic and about 90 in the United States. The second greatest area of oak diversity is China, with approximately 100 species. Description Oaks have spirally arranged leaves, with lobate margins in many species; some have serrated leaves or entire leaves with smooth margins. Man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variety (botany)
In botanical nomenclature, variety (abbreviated var.; in la, varietas) is a taxonomic rank below that of species and subspecies, but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if the taxon is seen throughout the geographic range of the species. Example The pincushion cactus, ''Escobaria vivipara'' (Nutt.) Buxb., is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about . Nine varieties have been described. Where the varieties of the pincushion cactus meet, they intergrade. The variety ''Escobaria vivipara'' var. ''arizonica'' is from Arizona, while ''Escobaria vivipara'' var. ''neo-mexicana'' is from New Mexico. See also '' Capsicum annuum var. glabriusculum'' Definitions The term is defined in different ways by different authors. However, the I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calybium And Cupule
The calybium and the cupule make up the accessory fruit of flowering plants in the family Fagaceae. These two parts derive from different flower components. The cupule holds and protects the fruit during its growth and maturation. In some genera (e.g. '' Lithocarpus, Quercus''), it only partly encloses the single nut, while in others (e.g. '' Castanea, Fagus''), it fully encloses the two or more nuts, and splits open at maturity into four valves to release the nuts. It is derived from the vegetative part of the flower (its attachment to the rest of the plant). It is covered by numerous scales. In some (e.g. ''Castanea''), the scales are developed into sharp spines, giving the nut protection from squirrels and other seed predators, while in others (e.g. most ''Quercus''), they are not. In ''Lithocarpus'', the cupule is very hard and bone-like in texture. The calybium (plural: calybia) is the fruit proper. It develops from an inferior ovary, meaning it is initially encased in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn
The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne in a cup-shaped 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 for details of oak classification, in which acorn morphology and phenology are important factors. Etymology The word ''acorn'' (earlier ''akerne'', and ''acharn'') is related to the 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. Chaucer spoke of "achornes of okes" in the 14th century. By degrees, popular etymology connected the word both with "corn" and "oak-horn", and the spelling changed accordingly. The current spelling (emerged 15c.-16c.), derives from asso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
