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The prairie is a vast grassland that sprawls across the central North American continent. It is one of three prairie regions in North America.In the U.S., the area is constituted by most or all of the states of North Dakota, South Dakota, Nebraska, Kansas, and Oklahoma, and sizable parts of the states of Montana, Wyoming, Colorado, New Mexico, Texas, Missouri, Iowa, Illinois, Indiana, Wisconsin, and western and southern Minnesota. The Palouse of Washington and the Central Valley of California are also prairies. The Canadian Prairies occupy vast areas of Manitoba, Saskatchewan, and Alberta. Prairies contain various lush flora and fauna, often contain rich soil maintained by biodiversity, with a temperate climate and a varied view. In certain districts, the subglacial till was not spread out in a smooth plain, but accumulated in elliptical mounds, 100–200 feet. high and 0.5 to 1 mile (0.80 to 1.61 kilometres) long with axes parallel to the direction of the ice motion as indicated by striae on the underlying rock floor. These hills are known by the Irish name, drumlins, used for similar hills in north-western Ireland. The most remarkable groups of drumlins occur in western New York, where their number is estimated at over 6,000, and in southern Wisconsin, where it is placed at 5,000. They completely dominate the topography of their districts.
Certain extraordinary features were produced when the retreat of the ice sheet had progressed so far as to open an eastward outlet for the marginal lakes. This outlet occurred along the depression between the northward slope of the Appalachian plateau in west-central New York and the southward slope of the melting ice sheet. When this eastward outlet came to be lower than the south-westward outlet across the height of land to the Ohio or Mississippi river, the discharge of the marginal lakes was changed from the Mississippi system to the Hudson system. Many well-defined channels, cutting across the north-sloping spurs of the plateau in the neighborhood of Syracuse, New York, mark the temporary paths of the ice-bordered outlet river. Successive channels are found at lower and lower levels on the plateau slope, indicating the successive courses taken by the lake outlet as the ice melted farther and farther back. On some of these channels, deep gorges were eroded heading in temporary cataracts which exceeded Niagara in height but not in breadth. The pools excavated by the plunging waters at the head of the gorges are now occupied by little lakes. The most significant stage in this series of changes occurred when the glacio-marginal lake waters were lowered so that the long escarpment of Niagara limestone was laid bare in western New York. The previously confluent waters were then divided into two lakes. The higher one, Lake Erie, supplied the outflowing Niagara River, which poured its waters down the escarpment to the lower, Lake Ontario. This gave rise to Niagara Falls. Lake Ontario's outlet for a time ran down the Mohawk Valley to the Hudson River. At this higher elevation, it was known as Lake Iroquois. When the ice melted from the northeastern end of the lake, it dropped to a lower level, and drained through the St. Lawrence area. This created a lower base level for the Niagara River, increasing its erosive capacity.
So now I finally know what a prairie is. Ecologists classify prairies as temperate grasslands, because they are characterized by plants and grasses rather than trees. But does it mean that prairie dog means meadow dog, plus I never new prairies are mainly found in the interior lowland areas of North America. In the United States, prairies can mainly be found in the area known as the Great Plains, which includes most of the states of North Dakota, South Dakota, Nebraska, Kansas, and Oklahoma. Prairies also constitute large parts of many other states, including Montana, Wyoming, Colorado, New Mexico, Texas, Missouri, Iowa, Illinois, Indiana, Wisconsin, and Minnesota. And they can cover almost 1.5 million square miles of land in the U.S. Rainfall decreases as you move from east to west. Eastern prairies tend to be moister, while western prairies are usually drier the closer they get to desert areas, amazing. But in Florida we have the Everglades. ;) ;) (Source: wonderopolis.org)