CROPS AND SOIL IMPROVEMENT 



acid. The market price is above agricultural 

 value, and any needed potash should be obtained 

 from the German potash salts. 



Other Fertilizers. Manufacturers of commer- 

 cial fertilizer make use of other materials, some of 

 which, like manufactured nitrogen, are excellent, 

 and others are low in quality and slow in action. 

 The sources of plant-food that have been described 

 form the great bulk of all fertilizers on the market, 

 and from them may be selected all the materials 

 a farmer needs to use on his land, either singly or 

 home-mixed. In most instances the selection 

 will embrace only four or five of these fertilizing 

 materials. 



Salt. Salt is not a direct fertilizer, and its 

 use is not to be advised unless it can be secured 

 at a very low price per ton. Some soils have been 

 made more productive by the application of 200 

 to 300 pounds per acre, and chiefly in case the 

 salt was mixed well with the soil when the seed- 

 bed was made. The practice of using salt as a 

 top-dressing on wheat in the spring gives less 

 effectiveness it is believed. Salt frees potash in 

 the soil, and may have some practical effect upon 

 soil moisture. As a soil amendment, salt has had 

 more reputation than its performance justifies. 



[186] 



