278 THE GEOLOGY OF MINNESOTA. 



[Soil and timber. 



never been stratified, or arranged with any regularity that would indicate 

 its having been deposited either by standing or running water. In most 

 cases, specially on the open prairie, it is nearly black. As it is mingled 

 with the drift clay it becomes lighter colored. In the low grounds it is 

 much thicker, and also of a black color. Overlapping the drift area in a 

 belt about five miles wide, is a soil formed by the mingling of the loess-loam 

 with the drift. The loess-loam is later than the glacial drift, and in the 

 process of deposition it is modified by contact with the drift clay. The 

 loess-loam is indistinctly stratified, though it usually appears massive, and 

 consists of fine, often clayey sediment. The soil derived from it, usually 

 sandy and light colored or rusty, is sometimes so clayey as to make, when 

 wet, a fine and very slippeiy mud. The soil derived distinctly from the 

 loess-loam covers at least one-half of the county, and is supposed to extend 

 to the Mississippi river. It makes a rich and apparently strong soil, as it 

 supports a cropping of wheat from year to year. It is impossible to define 

 its western limit. If it were derived from a long-standing inland lake some 

 beach-lines would be found indicating its western boundary. No beach- 

 lines have been found. That it was deposited from standing water can 

 hardly be questioned. It thins out westwardly gradually, passing through 

 a confused or mixed condition resulting from the mingling of the drift ma- 

 terials with the sediment, or by its overlapping the drift. While the essen- 

 tially loess-loam soil of the eastern part of the county, can be distinguished 

 easily from the drift soil of the western, no line of demarkation separating 

 them has been noticed. A line drawn from the southeast corner of Bristol 

 to the northeast corner of Jordan would roughly set off the area that has a 

 distinctively loess-loam soil. West of that is a belt of five or six miles wide, 

 in which the loess-loam soil mingles with the drift soil. The rest of the 

 county toward the west is occupied with a distinctively drift soil, or drift- 

 loam soil. 



Trees and shrubs of Fillmore county. 



The following list embraces such native trees and shrubs as were seen in the survey of the 

 county. The trees are arranged in the estimated order of frequency. The area covered by native 

 timber is steadily increasing. A large proportion of the county is covered with bushes which are 

 composed of hazel, aspen, oak (two sorts) and, where these are wanting, a species of low willow 

 which seems to come up first after the prairie fires are stopped. After the willow, hazel and oak 

 and aspen gradually come in, and in time convert the original prairie to a bushy or timbered re- 

 gion. Over some large tracts in the county this process is going on. There are thousands of acres 



