THE SOILS AND CEOPS OF THE FAKM. 



CHAPTER I. 



PLANT FOOD AND GROWTH. 



Plants live and grow. Growth comes from food. 

 Plant food must come fi'om, or through, the soil or 

 air, or both. Plants cannot move about to seek food. 

 They do not have mouths like those of animals. They 

 cannot take in solid substances. Their food must be 

 brought into contact with them and be either liquid 

 or gaseous in form. 



Finding out of what a plant is composed will 

 help to an understanding of how and from whence it 

 gets its food. 



Water is found in any living plant in larger 

 quantity than is any other substance. Generally 

 there is a greater quantity of water in a living plant 

 than of all other substances. This is true of all farm 

 crops while they are growing. Turnips or pump- 

 kins have more than nine- tenths of their weight 

 made up of water. There is less solid matter in 

 such vegetables than in milk. The percentage of 

 water in farm crops is much lessened when they have 

 been harvested and are ready for use, but there is 

 rarely less than ten per cent of water in either the 

 grain, stalk or leaf of farm crops when called thor- 

 oughly dry. To drive off all the wat6r from a plant 

 it must be exposed to a high temperature for many 

 hours. 



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