The North American Great Plains are one of the world's great mid-latitude grasslands.
In North American culture, "plains" often call to mind the vast, sere, rolling prairies that sprawl between the Rocky Mountains and the more well-watered Heartland -- the geographic region called the Great Plains immortalized in the journals of Oregon Trail emigrants and the rich semi-nomadic cultures indigenous to it. But a "plain," speaking strictly in geologic terms, is not synonymous with "grassland."
Topographic Plain
A "plain" in physical geography refers simply to a level or mostly level tract of land. Such a landform often materializes within the valley of a mature, meandering river in the guise of a floodplain built by repeated inundations of a high-flow river in flood. A coastal plain, such as that fringing the North American continent along the Gulf of Mexico and Atlantic Ocean, might be built by gentle marine and alluvial depositions. Florida's limestone plain is a karst peninsula that has been repeatedly drowned and exposed by changing sea levels in recent geologic history. The word "plain" by this definition makes no statement on the ecological landscape blanketing the topographic structure: A plain can be open and treeless or heavily forested.
Grasslands
Grasslands are ecological landscapes or ecosystems, not topographic landforms. As their name suggests, they are regions dominated by grasses and cover extensive acreage in both the tropics and temperate latitudes of the world. Mid-latitude grasslands sprawl across huge expanses of the North American and Eurasian interior while tropical grasslands are particularly notable in South America, Africa and Australia. In many of these places, topographic plains underlie the grasslands, but this isn't always be the case. Smaller-scale grasslands might carpet other landforms, as in the rolling foothill grasslands of mountain uplifts or the grassy balds dotting certain summits in the southern Appalachians.
The Great Plains
The broad belt of mid-latitude grasslands in the heart of the North American continent, stretching from Saskatchewan to northern Mexico, is called the Great Plains. They are indeed situated upon rolling country derived from ancient seaway beds and alluvial deposits off the nearby Rocky Mountains, thus "plain" is an appropriate topographic moniker. In historical and cultural parlance, however, the "Plains" have come to signify these vast oceans of grass, actually encompassing two major grassland types: the mixed-grass and short-grass prairies. The short-grass prairie stretches eastward from the foot of the Rocky Mountains, defined by low grasses adapted to semi-arid conditions. Eastward, mixed-grass prairie begins to predominate, forming a transition belt between the Great Plains and the moister tall-grass prairies of the Central Lowlands of the Midwest.
Other Grassland Synonymns
In America, "plains" may be a colloquial term for grasslands. Prairie, too, is a type of grassland, most commonly in reference to the grasslands of the Central Lowlands and Great Plains but also used for the Palouse country of the Columbia Basin in the interior Northwest. Other synonyms or specific types include steppe, a word mainly used in Eurasia but also commonly applied to the short-grass plains and intermountain sagebrush and bunchgrass country of North America; pampas, a South American grassland; and savanna, which is technically a type of grassland but often used in reference to grass-dominated habitats scattered with widely spaced trees.
Tags: Great Plains, North American, Rocky Mountains, American continent, called Great
