290 



Illinois State Dairymen's Association. 



Table 4. — Organic Matter of Soils. 



Percent of organic matter. 

 Soil areas, soil types. Surface Subsurface 



0-7 inches. 7-18 inches. 

 Unglaciated area of Southern Illinois — 



Yellow silt loam (timber) 1.66 .59 



Lower Illinois Glaciation — 



Gray silt loam (prairie) .... 

 Light-gray silt loam (timber) 

 Yellow silt loam (timber) . . . 



2.36 



1.06 



1.66 



.72 



1.88 



.74 



Lower Illinois Moraines — 



Yellow fine sandy loam (timber) 



2.72 



1.12 



Deep Loess Areas — 



Yellow fine sandy loam (timber) 



1.35 



.67 



Lower-Middle Illinois Glaciation — 

 Brown-gray silt loam (prairie) 



2.46 



1.73 



Middle Illinois Glaciation — 

 Black clay loam (prairie) 

 Brown silt loam (prairie) 



Gray silt loam 



Yellow-gray silt loam 

 Yellow silt loam (timber) 



timber 



Upper Illinois Glaciation — 

 Black clay loam (prairie) 

 Brown silt loam (prairie) 

 Light-gray silt loam .... 

 Yellow-gray silt loarn 

 Yellow silt loam 



timber. 



5.42 



3.05 



4.59 



2.98 



1.98 



.68 



1.35 



.71 



7.24 



4.87 



5.68 



3.45 



2.12 



.71 



Pre-Iowan Glaciation — 



Brown silt loam (prairie 

 Light-gray silt loam 



4.72 



2 29 



* The percent of organic carbon was multiplied by 1,724 to determine 

 the organic matter. 



Soil areas, soil types. 



lowan Glaciation — 



Brown silt loam (prairie) 



Light-gray silt loam 



Yellow-gray silt loam \ 

 Yellow silt loam ... ( timber 

 Yellow-gray silt looa ) 



Percent of organic matter 



Surface Subsurface 



0-7 inches. 7-18 inches. 



4.38 



2.14 



2.33 

 73 



