Category: Earth Science
The Great Plains refers to the large flat prairies of North America that stretch from the Missouri River to the Rocky Mountains in the west. The Great Plains stretch all the way from the southern edge of Texas into Canada, where they fade into the Arctic tundra and polar climate zone. The border for the Great Plains on the South is typically described as the Rio Grande river in Texas, though some consider it stretching into northern Mexico.
What’s In a Name?
The U.S. calls the Great Plains that name. Canada calls its portion of the “Great Prairies”.
The term “Great Plains” is used in reference to other related concepts. For example, the states of Kansas, Nebraska and others are called the “Plains States”. The Native Americans from that region are called the “Plains Indians”. Canada calls the provinces east of the Rockies and west of the Great Lakes the “Prairie Provinces”. A University of Nebraska program that studies the ecosystem is called the Center for Great Plains Studies.
Industries of the Great Plains
The Great Plains are part of the largest continuous stretch of fertile farmland in the world. They became the breadbasket of the world after aquifers like the Ogallala were tapped to water the Great Plains. Before this, they were referred to as a great inland desert for the relative lack of water except along the rivers. The Great Plains south of the Canada-U.S. border are primarily used to raise grains and soybeans except for areas too dry, thus used for grazing or left fallow. North of the Canadian border, land usage is primarily cattle ranges and grazing.
History of the Great Plains
Before the death of the dinosaurs 65 million years ago, the Great Plains were the bottom of an inland sea called the “Western Interior Seaway”, though it had begun to recede by 55 million years ago, leaving flat layers of sediment that shaped the relatively flat Great Plains of today.
During the Ice Ages, the Great Plains saw glaciations to the middle of the continent with cold dry grasslands extending south to the Texas coast. Areas like the Missouri Plateau were under deep layers of ice. The southern range from Kansas south were ice free and full of herbivores like wooly mammoths, wild horses (hunted to extinction by Native Americans prior to European arrivals), giant sloths and others. The megafauna were hunted to extinction by the time Europeans arrived except for the bison.
Before European settlement, the Great Plains were dominated by large buffalo herds. The large herds travelled in groups of thousands to millions, their regular passes preventing the growth of trees. While Native Americans did live in the Great Plains, it was not until the introduction of the horse than many tribes shifted to hunting buffalo for food. This is why many of the tribes readily known for their buffalo hunting were once Mississippi valley farmers.
The Great Plains suffer harsh, cold winters and hot, humid summers. The Great Plains are unusual in that they stretch from the warm coastal waters of Texas to the freezing Arctic waters north of Canada. This allows for rapid shifting between warm weather fronts and cold weather fronts and the creation of storm fronts between them. This is why the Great Plains are where 90% of all tornadoes on Earth occur. Most other large plains like those near Mongolia or Central Europe like those in Ukraine rarely have tornadoes.
The 100th meridian is a dividing line between areas that receive more than twenty inches of rainfall and that which receives less than twenty inches. The drier areas are better suited for grazing animals than agriculture without extensive irrigation.
The large dry areas give rise to large dust storms every few years.