The Osage Plains are a physiographic section

Physiographic regions of the world

The physiographic regions of the world are a means of defining the Earth's landforms into distinct regions based upon classic 1916 three-tiered approach defining divisions, provinces, and sections...

 of the larger Central Lowland province, which in turn is part of the larger Interior Plains

Interior Plains

The Interior Plains is a vast physiographic region that spreads across the Laurentian craton of central North America.-Geography:The Interior Plains are an extensive physiographic division encompassing 8 distinct physiographic provinces, the Interior Low Plateaus, Great Plains, Central Lowland,...

 physiographic division. The area is sometimes called the Lower Plains, North Central Plains, and the Rolling Plains. The Osage Plains, covering west-central Missouri

Missouri

Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...

, the southeastern third of Kansas

Kansas

Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...

, most of central Oklahoma

Oklahoma

Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...

, and extending into north-central Texas

Texas

Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

, is the southernmost of three tallgrass prairie

Tallgrass prairie

The tallgrass prairie is an ecosystem native to central North America, with fire as its primary periodic disturbance. In the past, tallgrass prairies covered a large portion of the American Midwest, just east of the Great Plains, and portions of the Canadian Prairies. They flourished in areas with...

 physiographic areas. It grades into savanna

Savanna

A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...

 and woodland to the east and south, and into shorter mixed-grass prairie to the west. The Osage Plains consist of three subregions. The Osage Plains proper occupy the northeast segment. Although sharply demarcated from the Ozark uplift

The Ozarks

The Ozarks are a physiographic and geologic highland region of the central United States. It covers much of the southern half of Missouri and an extensive portion of northwestern and north central Arkansas...

, the Plains are nonetheless a transitional area across which the boundary between prairie and woodland has shifted over time. In the central portion of the physiographic area lies the second subregion, the Flint Hills

Flint Hills

The Flint Hills, historically known as Bluestem Pastures or Blue Stem Hills, are a band of hills in eastern Kansas stretching into north-central Oklahoma, extending from Marshall County, Kansas and Washington County, Kansas in the north to Cowley County, Kansas and Osage County, Oklahoma in the south...

. This large remnant core of native tallgrass prairie is a rocky rolling terrain that run from north to south across Kansas and extends into Oklahoma. To the west and south of these hills are the Blackland Prairies

Texas blackland prairies

The Texas Blackland Prairies are a temperate grassland ecoregion located in Texas that runs roughly from the Red River in North Texas to San Antonio in the south.-Setting:...

 and Cross Timbers

Cross Timbers

The term Cross Timbers is used to describe a strip of land in the United States that runs from southeastern Kansas across Central Oklahoma to Central Texas...

. This vegetatively complex region of intermixed prairie and scrubby juniper

Juniper

Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the...

-mesquite

Mesquite

Mesquite is a leguminous plant of the Prosopis genus found in northern Mexico through the Sonoran Desert and Chihuahuan Deserts, and up into the Southwestern United States as far north as southern Kansas, west to the Colorado Desert in California,and east to the eastern fifth of Texas, where...

 woodland extends into north-central Texas

Texas

Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

. Bluestem prairies and oak-dominated savannas and woodlands characterize the natural vegetation in the Cross Timbers. Much of the area has been converted to agriculture, although expanses of oak

Oak

An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...

 forest and woodland are still scattered throughout the eastern portion of the subregion.

Birds in the Osage Plains include the threatened Greater Prairie-Chicken, Henslow's Sparrow

Henslow's Sparrow

Henslow's Sparrow, Ammodramus henslowii, is a small American sparrow.Adults have streaked brown upperparts with a light brown breast with streaks, a white belly and a white throat...

, Dickcissel

Dickcissel

The Dickcissel is a small American seed-eating bird in the family Cardinalidae. It is the only member of the genus Spiza, though some sources list another supposedly extinct species...

, Loggerhead Shrike

Loggerhead Shrike

The Loggerhead Shrike is a passerine bird. It is the only member of the shrike family endemic to North America; the related Northern Shrike occurs north of its range but also in the Palearctic....

, Field Sparrow

Field Sparrow

The Field Sparrow is a small sparrow.Adults have brown upperparts, a light brown breast, a white belly, wing bars and a forked tail. They have a grey face, a rusty crown, a white eye ring and a pink bill....

, Scissor-tailed Flycatcher

Scissor-tailed Flycatcher

The Scissor-tailed Flycatcher is a long-tailed insectivorous bird of the genus, whose members are collectively referred to as kingbirds. The kingbirds are a group of large insectivorous birds in the tyrant flycatcher family...

, Bell's Vireo

Bell's Vireo

The Bell's Vireo is a small North American songbird. It is 4-3/4 to 5 inches in length, dull olive-gray above and whitish below...

, Painted Bunting

Painted Bunting

The Painted Bunting is a species of bird in the Cardinal family, Cardinalidae, that is native to North America.-Taxonomy:...

 and Harris's Sparrow

Harris's Sparrow

The Harris's Sparrow, Zonotrichia querula, is a large sparrow.Their breeding habitat is the north part of central Canada . In fact, this bird is Canada's only endemic breeder...

. Wildfire suppression, overgrazing

Overgrazing

Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, or by overpopulations of native or non-native wild animals.Overgrazing reduces the...

 and the spread of exotic plants are the factors most negatively affecting priority bird habitat. The area now is managed almost exclusively for beef production with annual burns and intensive grazing practices that provide little of the habitat structure required to support many priority bird species.

Historically, fire, drought, and Plains Bison

Plains Bison

The Plains Bison or Common bison is one of two subspecies/ecotypes of the American Bison, the other being the Wood Bison . Furthermore, it has been suggested that the Plains Bison consists of a northern and a southern subspecies, bringing the total to three...

 were dominant ecological forces and had great influences on the vegetation from local to landscape scales. The Osage Plains and Flint Hills

Flint Hills

The Flint Hills, historically known as Bluestem Pastures or Blue Stem Hills, are a band of hills in eastern Kansas stretching into north-central Oklahoma, extending from Marshall County, Kansas and Washington County, Kansas in the north to Cowley County, Kansas and Osage County, Oklahoma in the south...

 were dominated historically by tallgrass prairie with scattered groves of Blackjack Oak (Quercus marilandica) in the uplands and along drainages. A variety of wetland

Wetland

A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

 types, including wet prairie, marsh

Marsh

In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

es and northern floodplain

Floodplain

A floodplain, or flood plain, is a flat or nearly flat land adjacent a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge...

 forests occurred along larger rivers. Today, much of the land in the Osage Plains is planted to maize

Maize

Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

 and soybean

Soybean

The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...

s, or has been converted to non-native grasses for pasture

Pasture

Pasture is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep or swine. The vegetation of tended pasture, forage, consists mainly of grasses, with an interspersion of legumes and other forbs...

 and hay

Hay

Hay is grass, legumes or other herbaceous plants that have been cut, dried, and stored for use as animal fodder, particularly for grazing livestock such as cattle, horses, goats, and sheep. Hay is also fed to pets such as rabbits and guinea pigs...

. Large expanses of tallgrass prairie

Tallgrass prairie

The tallgrass prairie is an ecosystem native to central North America, with fire as its primary periodic disturbance. In the past, tallgrass prairies covered a large portion of the American Midwest, just east of the Great Plains, and portions of the Canadian Prairies. They flourished in areas with...

 remain in the Flint Hills where relief is greater than in the Osage Plains subregion and the land less suitable for cropping.

Geology

The Osage Plains is underlain by soft shale

Shale

Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...

s with interbedded sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

s and limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

s of late Mississippian to Pennsylvanian

Pennsylvanian

The Pennsylvanian is, in the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly . As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain...

 age. Some of the rocks prevalent in the Osage Plains are Mississippian limestone, limestone shale, Ordovician

Ordovician

The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...

 dolomite

Dolomite

Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....

, and coal

Coal

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

. There are also clay and shale within the Pennsylvanian bedrock.

The area contained two major mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 areas. The biggest was the Tri-State Lead and Zinc Region, consisting of nearly 2000 sq mi (5,180 km²). This was the largest concentration of zinc

Zinc

Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 deposits anywhere in the world. Most mining sites have closed, mainly due to health and other environmental issues, but more than $1 billion worth of lead

Lead

Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

 and zinc were extracted from the area during the active mining days. The other major mining was for bituminous coal

Bituminous coal

Bituminous coal or black coal is a relatively soft coal containing a tarlike substance called bitumen. It is of higher quality than lignite coal but of poorer quality than Anthracite...

. But due to air quality standards, this region's coal is in low demand due to its high sulfur

Sulfur

Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...

content.