356 COUNTY A1STD REGIONAL GEOLOGY. 



the great river, are nevertheless quite different from it in some 

 respects. As one stands upon the uplands that border the 

 valley, the lowlands at its bottom, which average about a 

 mile in width, appear to be quite as flat as flood-plains 

 usually are, but upon going down upon them he finds in 

 almost all cases that they slope very gently and uniformly 

 from the valley-side to the stream, so that those portions 

 only that are immediately adjacent to the stream are reached 

 by the floods. This being the character of the lowlands of 

 these valleys they are nearly all tillable without drainage. 

 The undulatory slope of the valley-sides to the higher surface 

 being so gentle, the valley is broad and shallow, averaging 

 from three to four miles in width. Thus, although their 

 scenery is lacking in boldness, that portion of the county 

 traversed by these streams is one of delightful and quiet 

 beauty. 



The usual narrow belt of woodland skirts the immediate 

 banks of these streams as well as those of their larger 

 branches. That part of the county lying east of the West 

 Mshnabotany is with these exceptions, all prairie, including 

 lowland, slope, and upland alike; but the part lying west of 

 that river, and of the main stream below th^ confluence, 

 is well supplied with timber for fuel, fencing, and common 

 lumber. Besides the original forest trees that were of mature 

 growth when the country was first occupied by white men, 

 a dense growth of young trees of all the indigenous species 

 have sprung up, covering large areas, and are rapidly 

 encroaching upon the prairies wherever the fires have been 

 incidentally or intentionally prevented from continuing their 

 annual ravages. These trees are of the most vigorous and 

 rapid growth, although the soil that supports them is entirely 

 composed of that fine homogeneous material that everywhere 

 forms the soil and subsoil, extending to a depth far beyond 

 the possible reach of the rootlets of adult trees. This fact 

 shows conclusively that the original absence of trees upon 

 the prairies was not due to the fineness of prairie soil as 

 some have supposed. 



