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Oklahoma State's map was made with Internet Map Server technology (ArcIMS). When I started my map, this technology was not available; I made mine by making smart maps, turning them into dumb graphics, making image maps out of the dumb graphics, and then making html pages to put them in. This is one of the reasons I haven't updated the map very often--it is a cumbersome process.
However, after looking at OK State's map, I think there is still a place for mine on the web, so I am working, off and on, on a major update, which I hope to have completed before the end of summer 2005. Many of the links are out of date and others need to be added. I also want to add institutions that offer Associate degrees in geography or geographic technology, and to include Mexico.
To those of you who have been faithfully emailing me with corrections and additions, my thanks for your patience and apologies for the long delay
=Bachelor' Master's =Doctorate
Among the problems on the grasslands, average annual precipitation was much less than in the East, although violent storms accompanied by high winds, hail, and tornadoes were common. Blizzards with wintry blasts intensifying the cold drove the snow into immense drifts. The hot, dry winds of summer parched the soil and sometimes carried it away in great billowing clouds of dust.
The region's sparse natural water supply would not support tree vegetation except along the stream courses. Many of these streams were small and flowed only intermittently. Eastern farmers, accustomed to a plentiful supply of water for crops and animals, as well as ample wood for building, fencing, and heating, had to adapt to quite different conditions in their attempts to settle the Great Plains.
THE PLAINS ENVIRONMENT
The topography and vegetation of the grasslands is among the least varied to be found anywhere in the United States. Early settlers following the Oregon Trail could reach the Pacific coast in one season of travel, in part because the grasslands were so easy to cross. The region lies entirely within the interior lowlands physiographic province. The underlying sedimentary beds dip gently. Elevation increases gradually, almost imperceptibly, from east to west. Along the eastern margin, the elevation is only 500 meters, whereas in the west, Denver, Colorado, claims an altitude of more than 1,500 meters.
Physiographically, the largest portion of the Great Plains is the High Plains stretching along the western margin of the region from south Texas northward to southern Nebraska. Covered by a thick mantle of sediments that are often quite sandy and extremely porous, this section is generally flat. Only along streams such as at Scottsbluff on the Platte River in western Nebraska or at Palo Duro canyon on the Red River in northwest Texas has erosion resulted in substantial local relief. The Lake Agassiz Basin, formerly occupied by the largest of the Pleistocene lakes, is another exceptionally flat area and includes the valley of the Red River of the North in North Dakota and Minnesota.
Not all portions of the region are so unvarying topographically. The most obvious exception are the Black Hills of South Dakota and Wyoming. A large, dome-shaped area of eroded igneous rock, the Black Hills are associated both geologically and topographically with the Rocky Mountains to the west. In southern Texas, the Edwards Plateau is heavily eroded into a canyonlands landscape along its southeastern margin where it is adjacent to the coastal plain. In central and northwestern Nebraska, the Sand Hills offer a dense, intricate pattern of grass-covered sand dunes, many of which are well over 30 meters high. The dunes were created by sand blowing along the southern margins of continental glaciers during the Pleistocene. Badlands topography--extremely irregular features resulting from wind and water erosion of sedimentary rock--is widespread on the unglaciated Missouri Plateau from northern Nebraska northward to the Missouri River. North of the Missouri River and west of the Lake Agassiz Basin, the glaciated Missouri Plateau, although sometimes flat, is covered with ponds, moraines, and other glacial features.
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