66 Kansas Academy of Science. 



shifted enormous amounts of debris from the crushed strata 

 of the earth's crust pushed up in the Rocky Mountains ; third, 

 to the disintegration of the miscellaneous assortment of bowl- 

 ders, gravel and finer drift pushed into Kansas from the states 

 north, by the Kansan glacier; and lastly, to the myriads of 

 plants and animals that have used the calcium carbonate and 

 silica in solution for their skeletons, and then in the course of 

 nature laid down their skeletons in beds of limestone. 



Then, in turn, the shales, sandstones and limestones dis- 

 integrated where exposed to air and rain, and the various 

 subsoils were formed. The relationship is so close between 

 the subsoil and the underlying shale, sandstone or limestone, 

 except where running water or the wind has shifted the sub- 

 soil, that a map showing the shales, sandstones and limestones 

 of the state serves equally well for a map of clay subsoils, 

 sandy subsoils or calcareous subsoils. The overlying soils 

 differ from the subsoils chiefly in the possession of humus, 

 without which no crop, except some of the legumes, will ma- 

 ture. The fourth visible essential of soils and subsoils is 

 water, and the relationship between water and all growing 

 vegetation is so intimate that tillage is chiefly concerned in 

 conserving the water supply. The fifth essential of a produc- 

 tive soil and subsoil is porosity, that air may circulate freely 

 about the roots of plants. The best soils and subsoils, then, 

 must be composed of clay and sand to give consistency and 

 penetrability, and of humus to conserve air and water and to 

 serve as food for bacteria. 



KANSAS SOILS. 



The proper admixture of clay, sand and humus determines 

 the physical qualities of a fertile soil ; but these ingredients 

 may be present in best proportions and the soil remain unpro- 

 ductive. Certain chemicals must be present and be in solution 

 in water or not a plant will grow. The following compounds 

 serve two great purposes in the plant economy: 1. Water, 

 carbon dioxide, and the nitrates, sulphates and phosphates 

 furnish the chemical elements used in food elaboration. 2. 

 Compounds containing potash, iron, lime and magnesia to- 

 gether with common salt and silica are necessary in the chemi- 

 cal physiological processes, but are not found in plant foods. 



These minerals so essential to the continued existence of 

 plants and animals on the earth come directly or indirectly 

 from subjacent or neighboring rocks. As has been stated. 



