28 FIELD OPERATIONS OF THE BUREAU OF SOILS, 1919, 



considerable coarse sand and occasional pebbles are incorporated. 

 The iinderlyinu: drift material, occurrin*^ below the -'i-foot section, is 

 a yellowish-brown to •2:ray, mottled clay loam, highly calcareous and 

 containing; much coarse material. This type has developed under 

 conditions of restricted draiiia^^e Avhich have favored the accumula- 

 tion of large (piantities of organic matter in the surface soil and pre- 

 vented the rapid leaching and oxidation of the subsoil. 



The surface soil in the flatter areas is higli in silt and clay, and 

 frecjuently approaches a silty clay loam in texture. V>'liere the sur- 

 face relief is broken with low, moundlike elevations, much coarse 

 material is present in both surface soil and sul)Soil. 



Within areas of the Webster loam are many large irregular- 

 shaped depressions and formerly ponded areas oc<.upied by the 

 Webster silty clay loam. These two types, differentiated on the 

 basis of texture and drainage, merge so gradually in places that 

 the boundaries between them must often be more or less arbitrary. 



This type covers the greater part of the western half of the 

 county. In the southern half of the county it extends eastward 

 over the Wall Lake region to the morainic divide coming down 

 from the east-central part of the county. Smaller disconnected 

 areas are found in the northeastern corner of the county and 

 throughout the morainic region, generally bordering ponded areas 

 or poorly drained flats. 



Natural drainage is poorly developed, owing to the flat topog- 

 raphy, the only adequately drained parts being the low mounds 

 and ridges interspersed throughout the area. The run-off was 

 very slow imtil large ditches were dug to drain the numerous swales 

 and depressions in which water collected. 



This type forms some of the most desirable land in the State. 

 The soil is very retentive of moisture, and droughts have never 

 caused a crop failure. Excess o-f rainfall during the gi^owing season 

 is likely to cut down the crop yields materially. The soil is later 

 than the Carrington type, there being a difference of 5 to 10 days 

 in maturity of crops. 



Most of the type is in cultivated crops or tame grasses. In the 

 northeastern and northwestern parts of the county, on some of the 

 poorly drained areas, the original prairie grasses flourish. The only 

 forest areas are artificially i)lanted windbreaks and woodlots. 



Com is particularly suited to the Webster loam. It is grown 

 more extensively and can be grown continuously for longer periods 

 on this land than on other types. ' The yields range from 40 to 80 

 bushels per acre, with an average of about 50 bushels. Oats ordi- 

 narily produce from 40 to 75 bushels per acre, and timothy and 

 clover IJ to 1} tons per acre. Some clover and alfalfa are grown 

 and do well when the soils are well drained. Alfalfa vieldg from 



