44 FIELD OPERATIONS OF THE BUREAU OF SOILS, 1918. 



section the texture is a sand to coarse sand. In several locations, 

 as in the river bend 1^ miles north of Gladwin, there are patches 

 where sand has been deposited over the surface by overflow waters. 



In sees. 5 and 6, T. 75 N., R. 2 W., there is an area which varies from 

 the type as it occurs elsewhere. Here the surface soil is high in 

 organic matter, which for the most part is well decomposed, but the 

 proportion is not sufficiently high to class the soil as Muck. The 

 surface soil is shallow and underlain with gray, yellowish-brown, or 

 mottled gray and yellow, coarse sand. The area is lower than the land 

 to the northwest or southeast and is traversed through its approximate 

 center by a drainage ditch. To the southwest the subsoil seems to 

 become heavier, and the soil there is mapped as the Wabash loam. 



The Cass loam is developed in the first bottoms of both the Iowa 

 and Mississippi Rivers. It is associated with the Wabash loam or 

 with Wabash or Cass soils of heavier texture. The drainage is natu- 

 rally fair to good. The surface soil has sufficient coherency to re- 

 tain moisture quite well, but, owing to the porosity of the subsoil, 

 crops are likely to be affected by periods of prolonged drought. Un- 

 less protected by levee the type is subject to overflow 



The Cass loam is one of the most extensive types in the Iowa 

 River bottoms. The greater part of it is in cultivation, the remain- 

 der being used for pasture. Corn is the chief crop, followed by oats, 

 wheat, hay, and to a limited extent rye. The methods of handling 

 the type, the crop yields, and land values are practically the same 

 as in the case of the Wabash loam. 



CASS SILTY CLAY LOAM. 



The Cass silty clay loam, to a depth of 12 inches, is a dark-brown 

 to black silty clay loam or silty clay. Below this depth there 

 occurs a dark-brown silty clay loam, containing considerable sand, 

 mottled with bluish gray, and below this, beginning at about 17 

 inches, a yellowish-brown sandy loam mottled with gray. The 

 lower part of the subsoil in many places is a sand. 



This type occurs in areas of varying size well distributed over the 

 bottoms of the Iowa and Mississippi Rivers. The natural surface 

 drainage is poor to fair, but the underdrainage is in most cases 

 ample, owing to the porous nature of the subsoil and substratum. 

 By ditching and pumping off the drainage water, the land can in 

 most cases be reclaimed, though in a few places, as in sec. 4, T. 76 N., 

 R. 5 W., c{uicksand, occurring at a depth of 4 to 6 feet and kept 

 saturated by the rise of water from the river, renders the problem 

 more difficult. Unless leveed, all of the type is subject to overflow. 



The total extent of the Cass silty clay loam is small. Approxi- 

 mately one-half of it is in cultivation, and the remainder in woods 

 pasture. The forest growth includes black oak, soft maple, elm. 



