6 FERTILIZERS IN THE WEST 



and for this reason alone a good supply of phosphoric acid is 

 necessary for the production of all plants and fruits. It 

 stimulates the growth of seedlings, favors the formation of 

 fruit and brings about early maturity. In this respect its 

 effect is opposite to that of nitrogen. 



Potash is very important in regulating the vegetative 

 functions of the plant in a chemical and mechanical way, 

 being found in largest amounts at those points where actual 

 development is proceeding most rapidly. Potash is essential 

 to the formation of the so-called carbohydrates, sugar, starch, 

 and cellulose, and to the transformation of sugar into starch 

 and vice versa, without which vegetation could not exist. The 

 importance of these effects of potash is at once understood if 

 we consider that starch and sugar are the principal plant con- 

 stituents used as food for man and beast. Starch is the chief 

 component of potatoes, of corn and of the different cereals, 

 and sugar that of the sugar cane and sugar beet. The 

 formation of cellulose is essential to that of wood, and a lack 

 of potash manifests itself by the weakness and brittleness of 

 the woody parts of plants; this is of especial importance in 

 fruit growing. Here potash has the additional advantage 

 that it improves the quality of fruits, by making them more 

 fleshy and of better flavor. Fruit grown with the required 

 amount of potash also keeps and stands shipment better than 

 otherwise. Potash is of the greatest benefit in the production 

 of legumes and also of grasses where it favors the formation 

 of seed. It also renders plants more hardy and more re- 

 sistant to the attacks of insects and diseases. 



