|
Swallenia Alexandrae
''Swallenia'' is a rare genus of plants in the grass family, found only in Death Valley National Park, California. The only known species is ''Swallenia alexandrae'', known by the common names Eureka dunegrass and Eureka Valley dune grass. This genus was named for American botanist Jason Richard Swallen (1903-1991). The species was named for American philanthropist and paleontological collector Annie Montague Alexander. Description This is a rare plant endemic to Inyo County, California, where it is found on a single isolated dune system, the Eureka Valley Sand Dunes in the Eureka Valley of the Mojave Desert, within Death Valley National Park. Description ''Swallenia alexandrae'' is a coarse, tufted perennial grass which grows in sand from thick rhizomes. Its stiffly erect clums, sharp-leafed grass, and erect pale-colored panicle inflorescences are diagnostic. Endangered status This is a federally listed threatened species of the United States. The main threat to the species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jason Swallen
Jason Richard Swallen (May 1, 1903 -April 22, 1991) was an American botanist specializing in grasses. Born in Alliance, Ohio, Swallen graduated from Ohio Wesleyan University (AB 1924) and Kansas State Agricultural College (MS 1925). He spent two summers at the Michigan University Biological Station, then in 1925, he started as a botanist at the US Department of Agriculture, serving under the USDA's chief agrostologist A. S. Hitchcock and after Hitchcock's sudden death in 1935, Agnes Chase. Swallen practiced botany in California in 1927, and from the southwest United States to Yucatan, Mexico, in 1928, 1931 and 1932. In 1936, he published on the grasses of Honduras and Peten, Guatemala, and was promoted to associate botanist. From 1943 to 1945, he served in Brazil as agricultural production officer in the US Office of the Coordinator of Inter-American Affairs. In 1947, he became the curator of the Division of Grasses at the Smithsonian Institution and chaired the Botany Depa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizome
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow horizontally. The rhizome also retains the ability to allow new shoots to grow upwards. A rhizome is the main stem of the plant that runs underground horizontally. A stolon is similar to a rhizome, but a stolon sprouts from an existing stem, has long internodes, and generates new shoots at the end, such as in the strawberry plant. In general, rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes. A stem tuber is a thickened part of a rhizome or stolon that has been enlarged for use as a storage organ. In general, a tuber is high in starch, e.g. the potato, which is a modified stolon. The term "tuber" is often used imprecisely and is sometimes applied to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural History Of The Mojave Desert
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena. The word ''nature'' is borrowed from the Old French ''nature'' and is derived from the Latin word ''natura'', or "essential qualities, innate disposition", and in ancient times, literally meant "birth". In ancient philosophy, ''natura'' is mostly used as the Latin translation of the Greek word ''physis'' (φύσις), which originally related to the intrinsic characteristics of plants, animals, and other features of the world to develop of their own accord. The concept of nature as a whole, the physical universe, is one of several expansions of the original notion; it began with certain core applications of the word φύσις by pre-Socr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flora Of The California Desert Regions
Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or '' skin flora''. Etymology The word "flora" comes from the Latin name of Flora, the goddess of plants, flowers, and fertility in Roman mythology. The technical term "flora" is then derived from a metonymy of this goddess at the end of the sixteenth century. It was first used in poetry to denote the natural vegetation of an area, but soon also assumed the meaning of a work cataloguing such vegetation. Moreover, "Flora" was used to refer to the flowers of an artificial garden in the seventeenth century. The distinction between vegetation (the general appearance of a community) and flora (the taxonomic composition of a community) was first made by Jules Thurmann (1849). Prior to this, the two terms were used indiscriminately.Thurmann, J. (1849). ''Essai de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic Flora Of California
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Grasses Of California
Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (other) In arts and entertainment * Native (band), a French R&B band * Native (comics), a character in the X-Men comics universe * ''Native'' (album), a 2013 album by OneRepublic * ''Native'' (2016 film), a British science fiction film * ''The Native'', a Nigerian music magazine In science * Native (computing), software or data formats supported by a certain system * Native language, the language(s) a person has learned from birth * Native metal, any metal that is found in its metallic form, either pure or as an alloy, in nature * Native species, a species whose presence in a region is the result of only natural processes Other uses * Northeast Arizona Technological Institute of Vocational Education (NATIVE), a technology school district in the Arizona portion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Poaceae Genera
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, '' Amborella'', and in this genus there is only one species, namely ''Amborella trichopoda.' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloridoideae
Chloridoideae is one of the largest subfamilies of grasses, with roughly 150 genera and 1,600 species, mainly found in arid tropical or subtropical grasslands. Within the PACMAD clade, their sister group are the Danthonioideae. The subfamily includes widespread weeds such as Bermuda grass (''Cynodon dactylon'') or goosegrass (''Eleusine indica''), but also millet species grown in some tropical regions, namely finger millet (''Eleusine coracana'') and teff (''Eragrostis tef''). With the exception of some species in ''Ellisochloa'' and Eleusine indica, most of the subfamily's species use the C4 photosynthetic pathway. The first evolutionary transition from C3 to C4 photosynthesis in the grasses probably occurred in this subfamily, around 32 to 25 million years ago in the Oligocene. Phylogeny Relationships of tribes in the Chloridoideae according to a 2017 phylogenetic classification, also showing the Danthonioideae as sister group: The following genera have not been assigned t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic factors will include the availability of food and the presence or absence of predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Off-road Vehicle
An off-road vehicle, sometimes referred to as an overland or adventure vehicle, is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks. Other vehicles that do not travel on public streets or highways are generally termed off-highway vehicles, including tractors, forklifts, cranes, backhoes, bulldozers, and golf carts. Off-road vehicles have an enthusiastic following because of their versatility. Several types of motorsports involve racing off-road vehicles. The most common use of these vehicles is for sightseeing in areas distant from the pavement. The use of higher clearance and higher traction vehicles enables access on trails and forest roads that have rough and low traction surfaces. Off-road vehicles can typically ford through deeper waters (i.e., rivers or floodwaters) than on-road vehicles can. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Threatened Species
Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensation'', a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment. IUCN definition The International Union for Conservation of Nature (IUCN) is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories, depending on the degree to which they are threatened: *Vulnerable species *Endangered species * Critically endangered species Less-than-threatened categories are near threatened, least concern, and the no longer assigned category of conservation dependent. Species which have not been evaluated (NE), or do not have sufficient data ( data deficient) also are not considered ... [...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] |
.jpg "Click for more on -> Natural History Of The Mojave Desert")
.jpg "Click for more on -> Endemic Flora Of California")
.JPG "Click for more on -> Habitat")
