— 4— 



milk or water and yeast and make bread. Upon bread 

 our digestive organs can easily act. Now when we say 

 that plants use phosphorus and nitrogen, etc., as food, we 

 do not mean that they absorb these separately, but that 

 when compounded with other food elements and dissolved 

 in the soil moisture, these food elements are taken up by 

 the plant. 



For instance, the two gases, nitrogen and hydrogen, 

 combined form ammonia. This is absorbed by the plant 

 and the nitrogen helps it to make a strong stalk. Nitro- 

 gen is the most important food of plants, while the next 

 is phosphoric acid which makes hardy and fruitful plants. 

 Decaying vegetation aids the plants in getting phosphoric 

 acid, or it may be added to the soil in manures, bones and 

 phosphoric rocks which have been treated with acid. 

 Potash is another important plant food, making woody 

 tissue and starch. Wood ash contains all the potash 

 which the burned wood had absorbed while it was a grow- 

 ing tree, so it is a very valuable application to the soil. 



All of these plant foods, or fertilizers as they are 

 called in commerce, may be bought and put into the soil, 

 but your mother will tell you that it is cheaper to bake 

 than to buy bread. In all probability, mother nature has 

 stored away more food than all the growing crops in his 

 fields could use, if the farmer does his part by thorough 

 -cultivation of the soil, or tillage as it is called, and by 

 adding such fertilizers as are produced right on his own 

 farm. Nothing should be allowed to go to waste on the 

 farm. 



HOW SOIL IS MADE. 



Nature has more than one means at her command for 

 fining the hardest of granite. All of the bodies of run- 

 ning water are helping her by grinding the pebbles over 



