PRAIRIE, a treeless region in the Missis sippi Valley, adjacent to the forested area, so called since the time of the early French explor ers. The eastern border of the prairie region is an irregular line crossing Minnesota and Wis consin in a southeasterly direction and extending into western Indiana, thence crossing Illinois and Missouri southwesterly to the borders of Oklahoma and eastern Texas. From this forest line the prairies extend westward from 200 to 600 miles to the Great Plains, into which they merge quite imperceptibly. In general we may say that the characteristics of the prairies are intermediate between those of the adjacent for ests on the east and the plains on the west. The soil, climate, rainfall, etc., of the prairies are much like those of the western edge of the forests. As we go westward the soil becomes more sandy, the climate more ((continental° and the rainfall less, approaching the conditions which prevail on the plains.
The soil of the prairies is usually dark in color and rich in organic matter. It is com posed of very fine particles, and when dried after wetting becomes very hard. It contains much finely divided sand, and is generally some what deficient in clay. While very rich and often of great depth, it is by no means inex haustible, and the better classes of farmers have found it profitable to add fertilizers from time to time.
The climate of the prairies is somewhat more severe than that of the adjacent forest areas, on account of the free sweep of the winds which intensify the cold of winter as well as the heat of summer. The annual rainfall is about 30 inches, diminishing somewhat as we go west ward, and this is so distributed that by far the greater portion falls in the spring and summer.
Although the prairies are usually spoken of as treeless, this is not strictly true, since the streams are always fringed with trees, the tree less areas extending over the higher lands from stream to stream. Yet since these forest fringes are often confined to the deep narrow valleys in which the streams flow, they are often scarcely noticeable as one looks over the landscape. The vegetation of the prairies naturally divides itself into that of the open country and that of the woodlands. In the open country the grasses constitute the dominant vegetation, since they are mostly perennial, and very tenacious of life. The species which are most common are grams (Bouteloua oligostachya, B. curtipendula, B. hir sute), buffalo grass (Bulbuls dactyloides), drop seed grass (Sporobolus, of several species), wild June grass (Koeleria cristata), blue-stem (Andropogon, of several species), switch grass (Panicum virgatum), beard-grass (Aristida, of several species), Muhlenberg grass (Muhlen bergia, of several species), sand-grass (Calama grostis), porcupine-grass (Stipa spartea), Eaton grass (Estonia), spear-grasses (Poe), fescue grasses (Festuca), brome-grasses (Bromus), wheat-grasses (Agropyrum), and wild-rye (Elymus), each of many species. Altogether
about 150 native species of grasses grow upon the prairies, affording fine pasturage and hay for stock. In those portions of the prairies where the rainfall is abundant these grasses con stitute a continuous sod which completely covers the surface, but where there is less rain they are in isolated clumps or bunches, and are then called ((bunch grasses.x' In all prairies there are other plants which grow intermingled with the grasses, the most conspicuous of which are the golden-rods (Solidago rigida, S. serotina, S. canadensis, and other species), asters (Aster patens, A. sericeus, A. muitiflorus, and other species), sunflowers (Helianthus annuus, and other smaller species). A few shrubs are found scattered over the prairies, adding to the variety of the vegetation, most noticeable the wild roses, redroot (Ceanothus), and shoe-string (Amor phia canescens), the last so-called on account of its long tough roots which trouble the plowman.
The woodlands are usually found bordering the water courses. In some cases they con stitut•broad areas extending for many miles on each side of the streams, while in others they are narrow belts but a few rods in width, or even mere fringes along the stream-banks. The trees of the prairies are all of species which have wandered away from the eastern forests, and pushed up the streams to a greater or less distance. There are more species along the eastern side of the prairies, and their number decreases as we go westward. The common species are oaks, hickories, walnuts, willows, cottonwood, elms, maples and ashes. As a rule these trees are not as tall as those which occur in the heavy forests eastward, and they gen erally grow with more spreading tops. Oc casionally, however, trees of gigantic dimen sions are found in sheltered situations. Careful observation of the trees on the prairies shows that where they are protected from fires, stock and other adverse influences, they generally re produce so rapdily as gradually to extend the forest areas. In many places the forest belts along the streams are widening, and also push ing up the valleys. Since the stoppage of prairie fires this natural spreading of the forests has gone on rapidly, so that there is to-day more forest-covered land in some parts of the prairie country than when it was first visited by white men. The prairie lands are from 300 to 1,400 feet above sea-level and are broken by river channels which have been cut in places to depths of over 100 feet.