GROUP OF HEAVY SOILS. 
19 
CHAPTER II. 
GROUP OF HEAVY SOILS. 
SUPERIOR SILT LOAM. 
Extent and distribution .—This soil occupies a total area of 
about one township. Irregular tracts ranging in size from a 
few acres to five or six square miles extend across the eastern 
part of the county in a northeasternly and southwesternly di¬ 
rection. It occurs more extensively in T 24 N, R 19 E in the 
towns of Osborn, Freedom, Grand Chute, and Center. There 
are only a very few small patches in the west half of the county. 
Description— The surface soil of this type to a depth of 
about eight inches consists of a brown silt loam containing a 
considerable amount of organic matter. The surface soil is 
free from gravel and stones. The subsoil consists of a heavy 
compact pinkish red clay, which extends to a depth of over 
three feet. 
There are some variations in this soil, the chief one being the 
depth of the silty material over the heavy red clay subsoil. This 
may vary from four to five inches up to ten or twelve inches. 
There is also some variation in the amount of organic matter, 
the largest amount being found in areas which are slightly de¬ 
pressed. Aside from these variations, which are all of minor 
importance, the type is very uniform. 
Topography and drainage .—The surface of the Superior silt 
loam is level, or only very gently undulating, and because of 
the heavy character of the subsoil, natural drainage is some¬ 
what deficient. During spring, when heavy rains are common, 
the soil becomes saturated, hence it warms up more slowly than 
soils having a more rolling surface. Over a considerable part 
of this type tile drains could be installed to good advantage. 
Origin .—The material forming this soil has been derived 
largely from lacustrine (lake laid) material which was de¬ 
posited in quiet waters at a time when the Great Lakes stood 
