80 Effective Farming 



Lime for Soil Improvement 

 Uses of lime. 



Correcting soil acidity. 



Rendering plant-food available. 



Improving the physical condition of soil. 



Lime as an aid for legumes. 



Supplying calcium by lime. 

 Forms of lime. 

 Quantity of lime to apply. 



IN the preceding chapter we have studied the effect on the 

 soil of stable manures and green-crops. In this chapter we 

 are to consider the fertilizing materials purchased in the mar- 

 ket as commercial manufactured commodities. It is not pos- 

 sible always to obtain sufficient home manures, and often the 

 more concentrated materials of the market are specially needed. 

 Lands that have been long farmed are likely to profit much 

 by the application of commercial fertilizers. Some kinds of 

 crops also make special response to them. The intensive vege- 

 table-grower would hardly know how to farm without such 

 materials ; he must grow many of his crops quickly if they are 

 to be of good quality and be ready for an early market; the 

 readily available fertilizer aids him to secure these results. 

 The grain-farmer, on the other hand, has a longer season in 

 which to grow the crop, and the product may be held for the 

 market ; he may therefore use less fertilizer and let the plants 

 get the additional support from supplies already in the soil. 

 When very heavy yields are desired, market fertilizers may be 

 needed. Modern farming cannot be understood without a 

 clear understanding of the function and use of commercial 

 fertilizers. The use of lime for soil improvement is also 

 treated in this chapter. Lime is very important for this pur- 

 pose and in many sections more of it should be applied to the 

 soil. 



COMMERCIAL FERTILIZERS 



34. Use and misuse of fertilizers. The materials contain- 

 ing nitrogen, phosphorus, and potassium that are used as 



