562 IOWA DEPARTMENT OF AGRICULTURE. 



is the supply equal to the demand. Able-bodied young men have no diffi- 

 culty in securing worlv on well-managed farms at wages varying from 

 twenty-five to thirty dollars per month for the entire year. 



THE SOILS OF IOWA. 



With the exception of the northeastern part of the state, the whole sur- 

 face of Iowa has in times past been overrun by great continental ice sheets 

 similar to the ones now covering the surface of Greenland. The sheet of 

 earth debris left after the ice melted away is called glacial drift, or till, 

 and may easily be recognized by the fact that usually it is a rather stiff 

 clay containing pebbles of all sorts, as well as large boulders or "nigger 

 heads." In this respect it contrasts markedly with the loess, which very 

 rarely contains small pebbles. This glacial till is very thick; in Iowa 

 it averages 200 feet, and in some places is thought to be as much as 500 



The crop will soon be in the shuck and then the threshiny crew will pull into field. 



feet in thickness. Four ice sheets, each making a corresponding sheet of 

 glacial drift, invaded Iowa at different times, but only one, called the 

 Kansan, ever succeeded in covering the southern as well as the northern 

 counties of the state. As all these ice sheets did not come from exactly 

 the same direction, there is some difference in the character of the ma- 

 terial which they brought. 



The Wisconsin is the largest drift sheet in the state. It is for the 

 most part in practically the same condition in which it was left after 

 the enormous mass of ice which covered it melted away, except that it 

 is now covered with vegetation. A few. larger streaims, such as the Des 

 Moines river, flow across it, but these rivers are so new that their tribu- 

 taries do not extend very far back from their main channels. Nearly 

 the whole territory is as yet a monotonous stretch of prairie, liberally 

 dotted with undrained ponds, sloughs, and lakes, many of which contain 

 accumulations of unrotted peat. On both the eastern and western borders 

 of the area are stretches of low hills which are the terminal moraines 

 made by the ice sheet. 



The soil of this belt is principally a black loam, sandy in some places 

 and claj'ey in others. It is generally rich in the elements of plant food 

 and frequently contains small boulders. 



In consequence of the absence of natural drainage lines the surface 

 of this area is frequently so marshy and water-logged that agriculture 



