50 Mineral Nutrition of Plants 



elements. However, enough is known to make it safe to repeat that a 

 good soil is, indeed, a frugal custodian of all the nutrient elements. 



SOILS NEED ADEQUATE CAPITAL 



It is generally recognized that the success and survival of a business 

 venture depends primarily upon adequate working capital and good 

 management. In a sense, the same situation prevails in the case of a 

 soil serving as a medium for plant growth. Here, the supply of readily 

 available nutrient elements may be likened to working capital; the 

 moderately available, to negotiable bonds and securities; and the slowly 

 available, to fixed assets or investments in real estate. The farmer must, 

 of course, provide the management. 



If a soil, located favorably as regards climate and surface drainage, 

 is provided with an adequate supply of the essential plant nutrients in 

 readily available forms, it is really astounding how satisfactorily crops 

 will usually grow and how well unfavorable physical conditions of the 

 soil will in time become corrected. In this connection the writer has in 

 mind a specific case. In North Central Wisconsin there exists a large 

 area of podzolic soil called Spencer silt loam. This soil is strongly acid 

 throughout the profile, and is therefore low in its supply of available 

 bases, particularly potassium. Also, the subsoil or B horizon is very 

 compact and rather impervious to both water and roots. It was generally 

 surmised that successful alfalfa culture on this soil would never be pos- 

 sible, even if adequately limed and fertilized, because of the impervious 

 and poorly drained subsoil. 



About twenty years ago a farmer by the name of James Asplin 

 acquired some typical Spencer silt loam. Apparently sensing that the 

 soil lacked a lot of something, Mr. Asplin proceeded to apply about 

 twenty-five wagon loads (25 tons) per acre of wood ashes to his soil. 

 The ashes were obtained from a nearby sawmill and probably contained 

 about three per cent of potassium, 50 per cent of lime, and appreciable 

 amounts of phosphorus and other mineral nutrients. Thus, approxi- 

 mately 1500 pounds per acre of potassium in the form of the carbonate 

 and an abundant supply of readily available lime and other mineral 

 nutrients were provided. In other words, the soil was provided with 

 adequate working capital. 



