Tallgrass prairie

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Flowering big bluestem, a characteristic tallgrass prairie plant Tallgrass prairie flora Andropogon gerardii.jpg
Flowering big bluestem, a characteristic tallgrass prairie plant

The tallgrass prairie is an ecosystem native to central North America. Natural and anthropogenic fire, as well as grazing by large mammals (primarily bison), were historically agents of periodic disturbance, which regulates tree encroachment, recycles nutrients to the soil, and catalyzes some seed dispersal and germination processes. Prior to widespread use of the steel plow, which enabled large scale conversion to agricultural land use, tallgrass prairies extended throughout the American Midwest and smaller portions of southern central Canada, from the transitional ecotones out of eastern North American forests, west to a climatic threshold based on precipitation and soils, to the southern reaches of the Flint Hills in Oklahoma, to a transition into forest in Manitoba.


They were characteristically found in the central forest-grasslands transition, the central tall grasslands, the upper Midwest forest-savanna transition, and the northern tall grasslands ecoregions. They flourished in areas with rich loess soils and moderate rainfall around 30-35 inches (700–900 mm) per year. To the east were the fire-maintained eastern savannas. In the northeast, where fire was infrequent and periodic windthrow represented the main source of disturbance, beech-maple forests dominated. In contrast, shortgrass prairie was typical in the western Great Plains, where rainfall is less frequent, and soils are less fertile. Due to expansive agricultural land use, very little tallgrass prairie remains.

History of origin and demise

Retreating glaciers deposited the parent material for soil in the form of till, i.e. unsorted sediment, about 10,000 years ago. Wind-dropped loess and organic matter accumulated, resulting in deep levels[ citation needed ] of topsoil. Animals such as bison, elk, deer, and rabbits added nitrogen to the soil through urine and feces. Prairie dogs, a ground squirrel-like rodent considered to be a keystone species, dug tunnels that "aerated the soil and channeled water several feet below the surface". [1] For 5,000 to 8,000 years, more than 240 million acres (970,000 km2) of prairie grasslands were a major feature of the landscape. [2] Between 1800 and 1930, the vast majority was destroyed. Settlers transformed what they named "the Great American Desert" or "The Inland Sea" into farmland. Major reasons for the prairie's demise were the confined grazing pattern of European cattle versus bison, the near-extermination of prairie dogs, and the plowing and cultivation of the land, which breached tallgrass root systems and interrupted reproduction. Furthermore, extensive tile drainage has changed the soil's water content and hydrodynamics, and ongoing soil erosion results in its increasing loss.

Estimates differ of how much original tallgrass prairie survives, ranging from less than 1% mostly in "scattered remnants found in pioneer cemeteries, restoration projects, along highways and railroad rights-of-way, and on steep bluffs high above rivers" [1] to 4%.


Tallgrass prairie is capable of supporting significant biodiversity. Parts of the ecoregion are among the "top ten ecoregions for reptiles, birds, butterflies, and tree species. Tallgrass species are found in the understory layer." [3] Oak (blackjack oak (Quercus marilandica) and post oak (Q. stellata) ) and hickory tree species occur in some areas, but generally in moderate densities. Bison (Bison bison) were a dominant species. [3]

The tallgrass prairie biome depends on prairie fires, a form of wildfire, for its survival and renewal. [4] Tree seedlings and intrusive alien species without fire tolerance are eliminated by periodic fires. Such fires may either be set by humans (for example, Native Americans used fires to drive bison and improve hunting, travel, and visibility) or started naturally by lightning.


Tallgrass prairie in relation to the Great Plains
Shortgrass prairie
Mixed grass prairie
Tallgrass prairie United States Prairies.svg
Tallgrass prairie in relation to the Great Plains
  Tallgrass prairie

As its name suggests, the most obvious features of the tallgrass prairie are tall grasses, such as indiangrass ( Sorghastrum nutans ), big bluestem ( Andropogon gerardi ), little bluestem ( Schizachyrium scoparium ), and switchgrass ( Panicum virgatum ), which average between 4.9 and 6.6 ft (1.5 and 2 m) tall, with occasional stalks as high as 8.2 to 9.8 ft (2.5 to 3 m). Prairies also include a large percentage of forbs, such as lead plant ( Amorpha spp.), prairie rosinweed ( Silphium spp.), gayfeathers ( Liatris spp.), sunflowers ( Helianthus spp.), asters ( Aster and Symphyotrichum spp.), coneflowers ( Echinacea spp., and Rudbeckia spp.), and many other species.

Technically, prairies have less than 5–11%[ clarification needed ] tree cover.[ citation needed ] A grass-dominated plant community with 10–49% tree cover is a savanna.

After the steel plow was invented by John Deere, this fertile soil became one of America's most important resources. Over 95% of the original tallgrass prairie is now farmland.


Bison grazing on the 158 km (39,000-acre) Tallgrass Prairie Nature Preserve in Osage County, Oklahoma Tallgrass Prairie Nature Preserve in Osage County.jpg
Bison grazing on the 158 km (39,000-acre) Tallgrass Prairie Nature Preserve in Osage County, Oklahoma
A pink wild onion (Allium stellatum) -- blooms in the tallgrass prairie of Waubay Wetland Management District in South Dakota. Pink and White Beauty (7368796606).jpg
A pink wild onion ( Allium stellatum ) — blooms in the tallgrass prairie of Waubay Wetland Management District in South Dakota.

The tallgrass prairie survives in areas unsuited to plowing: the rocky hill country of the Flint Hills, which runs north to south through east-central Kansas; the eastern fringe of the Red River Valley (Tallgrass Aspen Parkland) in Manitoba and Minnesota; the Coteau des Prairies , which extends from South Dakota through Minnesota and into Iowa; and the far north portion of Oklahoma. In Oklahoma, the tallgrass prairie has been maintained by ranchers, who saw the hat-high grass as prime grazing area for cattle.

The 39,000-acre (158 km2) Tallgrass Prairie Preserve in Osage County, Oklahoma, and the somewhat smaller 10,900-acre (44.1 km2) Tallgrass Prairie National Preserve in Kansas, attempt to maintain this ecosystem in its natural form. They have reintroduced plains bison to the vast expanses of grass. [4] Other U.S. preserves include Midewin National Tallgrass Prairie in Illinois, Broken Kettle Preserve and Neal Smith National Wildlife Refuge in Iowa, Konza Prairie in Kansas, and Prairie State Park in Missouri. In eastern North Dakota is Sheyenne National Grassland, the only national grassland on the tallgrass prairie. Also, several small tallgrass prairie reservations are in Cook County, Illinois, including the National Natural Landmark, Gensburg-Markham Prairie. [5]

The original extent of tallgrass prairie in Canada was the 2,300-square-mile (6,000 km2) plain in the Red River Valley, southwest of Winnipeg in Manitoba (see map). [6] While most of Manitoba's tallgrass prairie has been destroyed through cultivation and urban expansion, relatively small areas persist. One of the largest blocks of remaining tallgrass prairie in Manitoba is protected by several conservation partners in a conservation area called the Tallgrass Aspen Parkland. The Manitoba Tall Grass Prairie Preserve, which occupies small portions of the municipalities of Stuartburn and Emerson – Franklin, forms a part of the Tallgrass Aspen Parkland. This preserve contains about 4,000 ha (9,900 acres) of tallgrass prairie, aspen parkland, and wetlands.

A small pocket of less than 1,200 acres (5 km2) of tallgrass prairie remains in the southwest corner of Windsor, Ontario, protected by Ojibway Park, and Spring Garden Area of Natural Scientific Interest, along with the interconnected parks: Black Oak Heritage Park, Ojibway Prairie Provincial Nature Reserve, and the Tallgrass Prairie Heritage Park. Aside from the Provincial Nature Reserve, all are operated by the City of Windsor's Parks and Recreation.


Considered the birthplace of ecological restoration, the first tallgrass prairie restoration was the 1936 Curtis Prairie at the University of Wisconsin-Madison Arboretum. [7] The UW Arboretum was the center of tallgrass prairie research through the first half of the 20th century, with the development of the nearby Greene Prairie, Aldo Leopold Shack and Farm and pioneering techniques like prescribed burning. [8] The latter half of the 20th century saw the growth of tallgrass prairie restoration beyond Wisconsin borders, with projects in Illinois such as at Knox College, and Fermi National Laboratory. These major tallgrass restoration projects marked restoration’s growth from isolated studies to widespread practice. Tallgrass prairie restoration efforts picked up wider public recognition in the 1980s, spurred by the publication of a book of appreciation, John Madson's Where the Sky Began: Land of the Tallgrass Prairie (1982). [9] Nonprofit organizations throughout the former tallgrass prairie region began to reserve or restore small remnants of native prairie. For example, the Native Prairies Association of Texas was founded in 1986 to locate, restore, and protect prairies in Texas; the group currently protects about 2,780 acres (11.3 km2) of Texas prairies. [10]

The Midewin National Tallgrass Prairie, founded in 1996 near Elwood, Illinois, was as of 2006 the largest tallgrass prairie restoration area in the United States. In Minnesota, Glacial Ridge National Wildlife Refuge was established in 2004. The core of the refuge is a preserved 5,000-acre (20 km2) tallgrass prairie remnant, and an additional 30,000 acres (121 km2) are either in the process of restoration or will be soon. According to The Nature Conservancy, so far, 100 wetlands have been restored and 8,000 acres (32 km2) of land have been seeded with native plant species. [11]

Several books have been published on tallgrass prairie restoration, including:

See also

Related Research Articles

Prairie ecosystems considered part of the temperate grasslands, savannas, and shrublands biome

Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type. Temperate grassland regions include the Pampas of Argentina, Brazil and Uruguay, and the steppe of Ukraine, Russia and Kazakhstan. Lands typically referred to as "prairie" tend to be in North America. The term encompasses the area referred to as the Interior Lowlands of Canada, the United States, and Mexico, which includes all of the Great Plains as well as the wetter, hillier land to the east.

Temperate grasslands, savannas, and shrublands Terrestrial habitat type defined by the World Wide Fund for Nature

Temperate grasslands, savannas, and shrublands is a terrestrial habitat type defined by the World Wide Fund for Nature. The predominant vegetation in this biome consists of grass and/or shrubs. The climate is temperate and ranges from semi-arid to semi-humid. The habitat type differs from tropical grasslands in the annual temperature regime as well as the types of species found here.

Grassland areas where the vegetation is dominated by grasses (Poaceae)

Grasslands are areas where the vegetation is dominated by grasses (Poaceae); however, sedge (Cyperaceae) and rush (Juncaceae) families can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur naturally on all continents except Antarctica. Grasslands are found in most ecoregions of the Earth. For example, there are five terrestrial ecoregion classifications (subdivisions) of the temperate grasslands, savannas, and shrublands biome (ecosystem).

Oak savanna Type of savanna-or lightly forested grassland- where oaks are the dominant trees

An oak savanna is a type of savanna-or lightly forested grassland- where oaks are the dominant trees. These savannas were maintained historically through wildfires set by lightning, humans, grazing, low precipitation, and/or poor soil.

Flint Hills landform

The Flint Hills, historically known as Bluestem Pastures or Blue Stem Hills, are a region in eastern Kansas and north-central Oklahoma named for the abundant residual flint eroded from the bedrock that lies near or at the surface. It consists of a band of hills stretching from Kansas to Oklahoma, extending from Marshall and Washington Counties in the north to Cowley County, Kansas and Kay and Osage Counties in Oklahoma in the south, to Geary and Shawnee Counties west to east. Oklahomans generally refer to the same geologic formation as the Osage Hills or "the Osage."

Aspen parkland vegetation zone

Aspen parkland refers to a very large area of transitional biome between prairie and boreal forest in two sections, namely the Peace River Country of northwestern Alberta crossing the border into British Columbia, and a much larger area stretching from central Alberta, all across central Saskatchewan to south central Manitoba and continuing into small parts of the US states of Minnesota and North Dakota. Aspen parkland consists of groves of aspen poplars and spruce interspersed with areas of prairie grasslands, also intersected by large stream and river valleys lined with aspen-spruce forests and dense shrubbery. This is the largest boreal-grassland transition zone in the world and is a zone of constant competition and tension as prairie and woodlands struggle to overtake each other within the parkland.

Midewin National Tallgrass Prairie

The Midewin National Tallgrass Prairie (MNTP) is a tallgrass prairie reserve and United States National Grassland operated by the United States Forest Service. The first national tallgrass prairie ever designated in the U.S. and the largest conservation site in the Chicago Wilderness region, it is located on the site of the former Joliet Army Ammunition Plant between the towns of Elwood, Manhattan and Wilmington in northeastern Illinois. Since 2015, it has hosted a conservation herd of American bison to study their interaction with prairie restoration and conservation.

Texas blackland prairies Ecoregion (WWF)

The Texas Blackland Prairies are a temperate grassland ecoregion located in Texas that runs roughly 300 miles (480 km) from the Red River in North Texas to San Antonio in the south. The prairie was named after its rich, dark soil.

Tallgrass Prairie Preserve

The Tallgrass Prairie Preserve, located in Osage County, Oklahoma near Foraker, Oklahoma, is owned and managed by The Nature Conservancy. It is protected as the largest tract of remaining tallgrass prairie in the world. The preserve contains 39,000 acres (160 km2) owned by the Conservancy and another 6,000 acres (24 km2) leased in what was the original tallgrass region of the Great Plains that stretched from Texas to Manitoba.

University of Wisconsin–Madison Arboretum

The University of Wisconsin–Madison Arboretum is a teaching and research facility of the University of Wisconsin–Madison and the site of historic research in ecological restoration. In addition to its 1,260 acres (5 km2) in Madison, Wisconsin, the Arboretum also manages 520 acres of remnant forests and prairies throughout Wisconsin.

Prairie restoration type of habitat conservation

Prairie restoration is a conservation effort to restore prairie lands that were destroyed due to industrial, agricultural, commercial, or residential development. For example, the U.S. state of Illinois alone once held over 35,000 square miles (91,000 km2) of prairie land and now just 3 square miles (7.8 km2) of that original prairie land is left.

Tallgrass Aspen Parkland

The Tallgrass Aspen Parkland is an ecoregion located in southeastern Manitoba and northwestern Minnesota. The area is characterized by a mosaic of habitat types, including tallgrass prairie, aspen woodland, sedge meadow wetlands, riparian woodland, and oak savanna. A number of endangered and threatened species occur in the area, including the western prairie fringed orchid and Dakota skipper. One of Minnesota's only wild elk herds utilizes the area as well.

Flora of Saskatchewan

The native flora of Saskatchewan includes vascular plants, plus additional species of other plants and plant-like organisms such as algae, lichens and other fungi, and mosses. Non-native species of plants are recorded as established outside of cultivation in Saskatchewan, of these some non-native species remain beneficial for gardening, and agriculture, where others have become invasive, noxious weeds. Saskatchewan is committed to protecting species at risk in Canada. The growing season has been studied and classified into plant hardiness zones depending on length of growing season and climatic conditions. Biogeographic factors have also been divided into vegetative zones, floristic kingdoms, hardiness zones and ecoregions across Saskatchewan, and natural vegetation varies depending on elevation, moisture, soil type landforms, and weather. The study of ethnobotany uncovers the interrelation between humans and plants and the various ways people have used plants for economic reasons, food, medicine and technological developments. The Government of Saskatchewan has declared 3 indigenous plants as provincial symbols.

Manitoba Tall Grass Prairie Preserve conservation area in Manitoba, Canada

The Manitoba Tall Grass Prairie Preserve is located in southeastern Manitoba near Gardenton and Vita, this is about 50 kilometres (31 mi) south of Steinbach, Manitoba. It is one of the last remaining stands of tallgrass prairie in Manitoba and is part of the Tallgrass Aspen Parkland conservation area in Manitoba and Minnesota. Several groups and organizations help in land preservation in the Manitoba Tall Grass Prairie such as the Nature Conservancy of Canada, Nature Manitoba, Environment Canada, Manitoba Conservation and the Manitoba Habitat Heritage Corporation.

East Central Texas forests Ecoregion (WWF) in US

The East Central Texas forests (33) is a small temperate broadleaf and mixed forests ecoregion almost entirely within the state of Texas, United States. The northern forests perimeter is partially within the southeast Oklahoma border.

Central forest–grasslands transition

The central forest–grasslands transition is a prairie ecoregion of the central United States, an ecotone between eastern forests and the North American Great Plains. It is a classification defined by the World Wildlife Fund.

Central tall grasslands

The Central tall grasslands are a prairie ecoregion of the Midwestern United States, part of the North American Great Plains.

The ecology of the Great Plains is diverse, largely owing to their great size. Differences in rainfall, elevation, and latitude create a variety of habitats including short grass, mixed grass, and tall-grass prairies, and riparian ecosystems.

Central Great Plains (ecoregion)

The Central Great Plains are a semi-arid prairie ecoregion of the central United States, part of North American Great Plains. The region runs from west-central Texas through west-central Oklahoma, central Kansas, and south-central Nebraska.

Northern mixed grasslands

The Northern Mixed Grasslands is one of 867 terrestrial ecoregions defined by the World Wide Fund for Nature. This ecoregion includes parts of the Canadian provinces of Saskatchewan and Manitoba, north-central and eastern North Dakota, most of east South Dakota, and small portions of western Minnesota in the American Great Plains. The United States Environmental Protection Agency (EPA) defines this ecoregion as the Northern Glaciated Plains.


  1. 1 2 Graham, Pam. Tallgrass Prairie . ProQuest Discovery Guides Released November 2011.
  2. "Microbes Beneath the Surface". Science Today: California Academy of Sciences. Retrieved 26 September 2014.
  3. 1 2 "Central forest-grasslands transition". Terrestrial Ecoregions. World Wildlife Fund.
  4. 1 2 Klinkenborg, Verlyn (April 2007). "Splendor of the Grass: The Prairie's Grip is Unbroken in the Flint Hills of Kansas". National Geographic.
  5. "Into the Wild: Indian Boundary Prairies". Chicago Wilderness Magazine. Fall 2008. Archived from the original on 14 April 2014.
  6. "Prairie Grasslands and Parkland". Environment Canada. 22 August 2008. Archived from the original on 27 May 2010.
  7. Jordan, III, W. R. (2011). Making nature whole : a history of ecological restoration. Washington, DC: Island Press. ISBN   9781610910422. OCLC   750183084.
  8. Court, F. E. (2012). Pioneers of ecological restoration : the people and legacy of the University of Wisconsin Arboretum. Madison: University of Wisconsin Press. ISBN   978-0299286637. OCLC   814694131.
  9. Madson, John (1982). Where the Sky Began: Land of the Tallgrass Prairie. Boston, Mass.: Houghton Mifflin Company.
  10. "Native Prairies Association of Texas". www.texasprairie.org. Retrieved 10 April 2018.
  11. "The Nature Conservancy - Glacial Ridge Project". Nature.org. Retrieved November 14, 2007.

Further reading