24 FIELD OPERATIONS OF THE BUREAU OF SOILS, 1018. 



depth. The lower subsoil is frequontly very tenacious. The bluish- 

 gray tone is in some places rather light and in others rather dark, the 

 latter seeming to be the case where the soil is wet. 



This is the predominant soil on the western upland. It occupies, 

 with the exception of the most nearly level areas, the less dissected 

 portions of the upland back from the bluffs, and in some cases ex- 

 extends uninterruptedly for several square miles. It generally ad- 

 joins the Grundy silty clay loam and Tama silt loam, but occasionally 

 borders the Lindley silt loam or Clinton silt loam, and in some cases 

 extends down a gentler slope. One of the more noticeable of the 

 slope areas adjoins the old Illinoian River channel. 



The topography varies from almost level to gently rollmg. Both 

 surface run-off and underdrainage are good over the greater part of 

 the type, though a few places on slopes are slightly seepy. While 

 tiling is not essential to crop production, many farmers have put in 

 tile and consider the investment profitable. 



The Grundy silt loam is one of the most important soil types in the 

 county. Between 90 and 95 per cent of it is in cultivation, the re- 

 mainder being used for building sites, feed lots, barn lots, and tem- 

 porary pasture. The type is preeminently a corn soil, and one of the 

 best in the corn belt. Other important crops grown are oats, hay, and 

 wheat. Cattle raising and feeding and the other less important 

 branches of live-stock farming are well developed on this soil. 



Corn yields ^ range from 35 to 75 bushels per acre and average about 

 45 bushels. Higher yields have been made in a few instances. Oats 

 yield 35 to 75 bushels, with an average of about 50 bushels. Clover 

 and timothy range in yield from three-fourths ton to 2 tons, with an 

 average of 1^ tons. Spring wheat yields 10 to 40 bushels, with an 

 average of about 25 bushels. By following the proper methods, 

 alfalfa can be grown, and it is produced to a small extent. The 

 average yield for the season is about 2f tons per acre. 



Land of this type sells at $150 to $300 an acre,^ with an average of 

 $180 an acre. The price varies with the improvements and the near- 

 ness to towns and lines of transportation. 



GRUNDY SILTY CLAY LOAM. 



The Grundy silty clay loam has a surface soil of dark-brown to 

 black silty clay loaai, underlain at a depth of 12 inches by a black, 

 heavy, plastic silty clay, which at IS inches becomes dark gray, 

 mottled with pale grayish yellow and rusty brown. With increased 

 depth the subsoil becomes increasingly heavy and plastic and the pale 



8 Yields for this and other soil types are estimated from State crop reports, TT S. Census data, and the ob- 

 servations of field men during the progress of the survey. 



9 Land values as stated for this and other soil types are based in part on reported land sales and in part on 

 observations of the field men during the progress of thesurvcy. 



