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Hesperostipa Spartea
''Hesperostipa spartea'', formerly ''Stipa spartea'', is a species of grass known by the common names porcupine grass, western porcupine grass, short-awn porcupine grass, porcupine needlegrass, and big needlegrass. It is native to North America, where it is widespread from British Columbia to Ontario in Canada and through the central and Great Lakes regions of the United States. It is a bunchgrass species in the genus ''Hesperostipa''.USDA - ''Hesperostipa spartea'' . accessed 6.26.2012 Distribution ''Hesperostipa spartea'' is native to the and |
Carl Bernhard Von Trinius
Carl Bernhard von Trinius (6 March 1778, Eisleben – 12 March 1844, St. Petersburg) was a German-born botanist and physician. He studied medicine at several universities, earning his medical doctorate at the University of Göttingen in 1802. In 1808, after time spent as a physician in Hasenpoth, he served as a personal physician to Antoinette, Duchess of Württemberg (née Princess of Saxe-Coburg-Saalfeld) for the next 16 years. During this time period, he traveled extensively throughout Germany and Russia. In St. Petersburg, he became good friends to author Ernst Moritz Arndt. After the death of the duchess in 1824, he remained in St. Petersburg as an imperial physician, and along with a medical practice, he dealt with botanical concerns at the Academy of Sciences.biography @ |
Dominance (ecology)
Ecological dominance is the degree to which one or several species have a major influence controlling the other species in their ecological community (because of their large size, population, productivity, or related factors) or make up more of the biomass. Most ecological communities are defined by their dominant species. *In many examples of wet woodland in western Europe, the dominant tree is alder ('' Alnus glutinosa''). *In temperate bogs, the dominant vegetation is usually species of ''Sphagnum'' moss. *Tidal swamps in the tropics are usually dominated by species of mangrove (''Rhizophoraceae'') *Some sea floor communities are dominated by brittle stars. *Exposed rocky shorelines are dominated by sessile organisms such as barnacles and limpets. See also * National Vegetation Classification, a system for classifying British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panicle
A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are often racemes. A panicle may have determinate or indeterminate growth. This type of inflorescence is largely characteristic of grasses such as oat and crabgrass, as well as other plants such as pistachio and mamoncillo. Botanists use the term paniculate in two ways: "having a true panicle inflorescence" as well as "having an inflorescence with the form but not necessarily the structure of a panicle". Corymb A corymb may have a paniculate branching structure, with the lower flowers having longer pedicels than the upper, thus giving a flattish top superficially resembling an umbel. Many species in the subfamily Amygdaloideae, such as hawthorns and rowans, produce their flowers in corymbs. up'' Sorbus glabrescens'' corymb with fruit See ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. The stem holding the whole inflorescence is called a peduncle. The major axis (incorrectly referred to as the main stem) above the peduncle bearing the flowers or secondary branches is called the rachis. The stalk of each flower in the inflorescence is called a pedicel. A flower that is not part of an inflorescence is called a solitary flower and its stalk is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperostipa Comata
''Hesperostipa comata'', commonly known as needle-and-thread grass, is a species of grass native to North America, especially the western third. It has a wide distribution spanning from northern Canada to Mexico. Description ''Hesperostipa comata'' is a perennial bunchgrass producing erect, unbranched stems to about in maximum height. The narrow inflorescence is up to long in taller plants, with the mature spikelet bearing a spiraling, hairy, spear-shaped awn up to in length. The seeds of this grass have hygroscopic extensions that bend with changes in humidity, enabling them to disperse over the ground. Each seed has an awn that twists several turns when the seed is released. Increased moisture causes it to untwist, and, upon drying, to twist again, thus the seed is drilled into the ground. Habitat This is a grass of many habitat types, from grassland to pine forest. Young shoots provide a favored food source for black-tailed prairie dogs and black-tailed jackrabbits, and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gopher (animal)
Pocket gophers, commonly referred to simply as gophers, are burrowing rodents of the family Geomyidae. The roughly 41 speciesSearch results for "Geomyidae" on thASM Mammal Diversity Database are all endemic to North and Central America. They are commonly known for their extensive tunneling activities and their ability to destroy farms and gardens. The name "pocket gopher" on its own may refer to any of a number of genera within the family Geomyidae. These are the "true" gophers, but several ground squirrels in the distantly related family Sciuridae are often called "gophers", as well. The origin of the word "gopher" is uncertain; the French ''gaufre'', meaning waffle, has been suggested, on account of the gopher tunnels resembling the honeycomb-like pattern of holes in a waffle; another suggestion is that the word is of Muskogean origin. Description Gophers weigh around , and are about in body length, with a tail long. A few species reach weights approaching . Within any sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Succession
Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades (for example, after a wildfire) or more or less. Bacteria allows for the cycling of nutrients such as carbon, nitrogen and sulphur. The community begins with relatively few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community. The "engine" of succession, the cause of ecosystem change, is the impact of established organisms upon their own environments. A consequence of living is the sometimes subtle and sometimes overt alteration of one's own environment. Succession is a process by which an ecological community undergoes more or less orderly and predictable changes following a disturbance or the initial colonization of a new habitat. Succession may be initiated either by formation of new, unoccupied habitat, such as from a lava flow or a severe lan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climax Species
Climax species, also called late seral, late-successional, K-selected or equilibrium species, are plant species that can germinate and grow with limited resources; e.g., they need heat exposure or low water availability. They are the species within forest succession that are more adapted to stable and predictable environments, and will remain essentially unchanged in terms of species composition for as long as a site remains undisturbed. The seedlings of climax species can grow in the shade of the parent trees, ensuring their dominance indefinitely. The presence of climax species can also reduce the prevalence of other species within an ecosystem. However, a disturbance, such as fire, may kill the climax species, allowing pioneer or earlier successional species to re-establish for a time. They are the opposite of pioneer species, also known as ruderal, fugitive, opportunistic or R-selected species, in the sense that climax species are good competitors but poor colonizers, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pioneer Species
Pioneer species are hardy species that are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by wildfire. Pioneer flora Some lichens grow on rocks without soil, so may be among the first of life forms, and break down the rocks into soil for plants.LICHEN BIOLOGY AND THE ENVIRONMENT, LICHENS OF NORTH AMERICA, Sylvia and Stephen Sharnoff/ref> Since some uninhabited land may have thin, poor quality soils with few nutrients, pioneer species are often hardy plants with adaptations such as long roots, root nodes containing Diazotroph, nitrogen-fixing bacteria, and leaves that employ transpiration. Note that they are often photosynthetic plants, as no other source of energy (such as other species) except light energy is often available in the early stages of succession, thus making it less likely for a pioneer species to be non-photosynthetic. The plants that are often pioneer species also tend to be wind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizachyrium Scoparium
''Schizachyrium scoparium'', commonly known as little bluestem or beard grass, is a species of North American prairie grass native to most of the contiguous United States (except California, Nevada, and Oregon) as well as a small area north of the Canada–United States border, Canada–US border and northern Mexico. It is most common in the Midwestern United States, Midwestern prairies and is one of the most abundant native plants in Texas grasslands. Little bluestem is a perennial bunchgrass and is prominent in tallgrass prairie, along with big bluestem (''Andropogon gerardi''), indiangrass (''Sorghastrum nutans'') and switchgrass (''Panicum virgatum''). It is a C4 carbon fixation, warm-season species, meaning it employs the C4 photosynthetic pathway. Description Little bluestem grows to become an upright, roundish mound of soft, bluish-green or grayish-green blades in May and June that is about two to three feet high. In July, it initiates flowering stalks, which reach four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Festuca Altaica
''Festuca altaica'', synonym ''Festuca scabrella'', is a perennial bunchgrass with a wide native distribution in the Arctic, from central Asia to eastern North America. It has been called altai fescue and, under the synonym ''F. scabrella'', rough fescue. Description ''Festuca altaica'' is a densely tufted perennial grass. The tufts are connected by short rhizomes. The flowering stems ( culms) are usually tall, but may reach . The upper (adaxial) surface of the leaves is densely covered with short hairs. A ligule is present and is long. The inflorescence is a loose panicle. The spikelets are long, purple to brown in color, and have 3 to 6 individual florets. ''Festuca altaica'' flowers and fruits from late spring to the fall. Taxonomy ''Festuca altaica'' was first described in 1829 by Carl Bernhard von Trinius, who wrote the section on grasses in ''Flora Altaica'', whose principal author was Carl Friedrich von Ledebour. ''Festuca scabrella'' was described in 1840 by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
