POTASH FERTILIZERS 



219 



IN 10,000 POUNDS OF WOOD 



254. Action of Ashes on Soils. Ashes act upon soils 

 both chemically and physically. They are usually re- 

 garded as a potash fertilizer only, but they also contain 

 lime and phosphoric acid, and may be very beneficial 

 in supplying these elements. The potash is present 

 mainly as potassium carbonate. Ashes are valuable, 

 too, because they add alkaline matter to the soil, which 

 corrects acidity and aids nitrification. A dressing of 

 ashes improves the mechanical condition of many soils 

 by binding together the soil particles. This property 

 is. well illustrated in the so-called Gumbo soils, which 

 contain so much alkaline matter that the soil has a soapy 

 taste and appearance, and when plowed the particles fail 

 to separate. 



255. Leached Ashes. - - When ashes are leached the 

 soluble salts are extracted ; the insoluble matter which 

 is left is composed mainly of calcium carbonate and 

 silica. 66 



