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Boston Mountains
The Boston Mountains is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in the U.S. states of Arkansas and Oklahoma. Part of the Ozarks, the Boston Mountains are a deeply dissected plateau. The ecoregion is steeper than the adjacent Springfield Plateau to the north, and bordered on the south by the Arkansas Valley. The Oklahoma portion of the range is locally referred to as the Cookson Hills. There are several theories of how the mountains were named, though apparently none are related to the Massachusetts city. The Boston Mountains ecoregion has been subdivided into two Level IV ecoregions. Description The ecoregion is mountainous, forested, and underlain by Pennsylvanian sandstone, shale, and siltstone. It is one of the Ozark Plateaus; some folding and faulting has occurred but, in general, strata are much less deformed than in the Ouachita Mountains. Maximum elevations are higher, soils have a warmer temperature regime, and carbonate ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buffalo National River
The Buffalo National River, in Northern Arkansas, was the first National River to be designated in the United States. The Buffalo River is long. The lower flow within the boundaries of an area managed by the National Park Service, where the stream is designated the Buffalo National River. The river flows through Newton, Searcy, Marion, and Baxter Counties, from west to east. The river originates in the highest part of the Boston Mountains of the Ozarks, flows out onto the Springfield Plateau near the historic community of Erbie, and finally crosses a portion of the Salem Plateau just before joining the White River. The Park is home to the state's only elk herd. The upper section of the river in the Ozark National Forest is managed by the U.S. Forest Service and is designated as a National Scenic River and a National Wild River. History The Buffalo National River was established by an Act of Congress on March 1, 1972, ending the recurring plans of the U.S. Army Corp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers (Lamination (geology), laminae) less than one centimeter in thickness. This property is called ''Fissility (geology), fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the narrower sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Ozarks
The Ozarks, also known as the Ozark Mountains, Ozark Highlands or Ozark Plateau, is a physiographic region in the U.S. states of Missouri, Arkansas, and Oklahoma, as well as a small area in the southeastern corner of Kansas. The Ozarks cover a significant portion of northern Arkansas and most of the southern half of Missouri, extending from Interstate 40 in central Arkansas to Interstate 70 in central Missouri. There are two mountain ranges in the Ozarks: the Boston Mountains of Arkansas and Oklahoma, as well as the St. Francois Mountains of Missouri. Wahzhazhe Summit (formerly known as Buffalo Lookout), is the highest point in the Ozarks at , and is located in the Boston Mountains, in the westernmost part of Newton County, Arkansas, east of Boston, Madison County, Arkansas. Geologically, the area is a broad dome with the exposed core in the ancient St. Francois Mountains. The Ozarks cover nearly , making it the most extensive highland region between the Appalachians and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physiographic Regions Of The World
Physiographic regions are a means of defining Earth's landforms into independently distinct, mutually exclusive areas, independent of political boundaries. It is based upon the classic three-tiered approach by Nevin M. Fenneman in 1916, that separates landforms into physiographic divisions, physiographic provinces, and physiographic sections. The classification mechanism has become a popular geographical tool in the United States, indicated by the publication of a USGS shapefile that maps the regions of the original work and the National Park Services's use of the terminology to describe the regions in which its parks are located. Originally used in North America, the model became the basis for similar classifications of other continents. Physiography During the early 1900s, the study of regional-scale geomorphology was termed "physiography". Physiography later was considered to be a portmanteau of "''physi''cal" and "ge''ography''", and therefore synonymous with physica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortleaf Pine
The shortleaf pine or ''Pinus echinata'' is a species of coniferous tree endemic to the United States. The shortleaf pine is sometimes referred to as the "old field", "spruce", "rosemary", "yellow", "two-leaf" and "heart" pine. The common name "shortleaf pine" may refer to other species like loblolly pine (''Pinus taeda''), based on a custom in the Southeastern United States to only refer to pines as either "long-leaf" or "short-leaf". However, ''P. echinata'' can be distinguished from other pines by examining its short leaves and small cones. Description The tree is variable in form, sometimes straight, sometimes crooked, with an irregular crown. The tree reaches heights of . In areas that have optimal growing conditions, the height reached is between . The trunk diameter ranges between and averages between . The leaves are needle-like, in fascicles (bundles) of two and three mixed together, and from long. The cones are long, with thin scales with a transverse keel and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Oak
''Quercus'' subgenus ''Quercus'' is one of the two subgenera into which the genus ''Quercus'' was divided in a 2017 classification (the other being subgenus ''Cerris''). It contains about 190 species divided among five sections. It may be called the New World clade or the high-latitude clade; most species are native to the Americas, the others being found in Eurasia and northernmost North Africa. Description Members of subgenus ''Quercus'' are distinguished from members of subgenus ''Cerris'' by few morphological features, their separation being largely determined by molecular phylogenetic evidence. All are trees or shrubs bearing acorn-like fruit in which a cup covers at least the base of the nut. The outer structure of the mature pollen is one feature that distinguishes the two subgenera: in subgenus ''Quercus'', the small folds or wrinkles (rugulae) are obscured by sporopollenin, whereas in subgenus ''Cerris'', the rugulae are visible or at most weakly obscured. The two sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Red Oak
''Quercus falcata'', also called southern red oak, spanish oak, bottomland red oak or three-lobed red oak is an oak (part of the genus ''Quercus''). Native to the southeastern United States, it gets its name the "Spanish Oak" as these are the areas of early Spanish colonies, whilst "southern red oak" comes from both its range and leaf color during late summer and fall. The southern red oak is a deciduous angiosperm, so has leaves that die after each growing period and come back in the next period of growth. Description ''Quercus falcata'' is a medium to large-sized deciduous tree tall, with a few forest grown specimens on highly productive sites reaching , with a trunk up to in diameter, the crown with a broad, round-topped head. The leaves are long and wide, with 3 to 5 sharply pointed, often curved, bristle-tipped lobes, the central lobe long and narrow; the small number of long, narrow lobes is diagnostic, readily distinguishing southern red oak from other red oaks. The b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Red Oak
''Quercus rubra'', the northern red oak, is an oak tree in the red oak group (''Quercus'' section ''Lobatae''). It is a native of North America, in the eastern and central United States and southeast and south-central Canada. It has been introduced to small areas in Western Europe, where it can frequently be seen cultivated in gardens and parks. It prefers good soil that is slightly acidic. Often simply called red oak, northern red oak is so named to distinguish it from southern red oak (''Q. falcata''), also known as the Spanish oak. Northern red oak is sometimes called champion oak. Description In many forests, ''Quercus rubra'' grows straight and tall, to , exceptionally to tall, with a trunk of up to in diameter. Open-grown trees do not get as tall, but can develop a stouter trunk, up to in diameter. It has stout branches growing at right angles to the stem, forming a narrow round-topped head. Under optimal conditions and full sun, northern red oak is fast growing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultisols
Ultisol, commonly known as red clay soil, is one of twelve soil orders in the United States Department of Agriculture soil taxonomy. The word "Ultisol" is derived from "ultimate", because Ultisols were seen as the ultimate product of continuous weathering of minerals in a humid, temperate climate without new soil formation via glaciation. They are defined as mineral soils which contain no calcareous (calcium carbonate containing) material anywhere within the soil, have less than 10% weatherable minerals in the extreme top layer of soil, and have less than 35% base saturation throughout the soil. Ultisols occur in humid temperate or tropical regions. While the term is usually applied to the red clay soils of the Southern United States, Ultisols are also found in regions of Africa, Asia, Australia and South America. In the World Reference Base for Soil Resources (WRB), most Ultisols are known as Acrisols and Alisols. Some belong to the Retisols or to the Nitisols. Aquults are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
