18 ELEMENTS OF FARM PRACTICE 



Plant food is thus made soluble much more rapidly in 

 a soil that contains a good supply of vegetable matter, as 

 new sod land, than in an old soil from which much of the 

 vegetable matter has been used. 



Many soils that have produced grain and corn a great, 

 many years without the addition of manure have become 

 nearly depleted of vegetable matter; and, while they usually 

 contain plenty of plant food, it is in an insoluble form and 

 plants cannot make use of it. 



Adding Vegetable Matter. — A farmer can add vege- 

 table matter to his soil by growing on it once in every few 

 years such crops as clover, timothy and other grass crops. 

 These crops grow more than one year and consequently 

 have a large root system. These roots add a large supply 

 of vegetable matter; so several crops of corn or grain can 

 be grown successfully following a crop of grass. The 

 application of barnyard manure is another way by which 

 the farmer can put vegetable matter in the soil and thereby 

 increase its producing power. 

 Questions: 



1. What do you understand by the term vegetable matter in the 

 soil? 



2. In what way does vegetable matter assist in making plant 

 food soluble? 



3. In what ways may a farmer add vegetable matter to the soil? 

 Arithmetic: 



1 . How many lbs. of water in 20 bus. of wheat? 

 (Note: There are 12 lbs. of water in 100 lbs. of wheat.) 

 ^•. If 70% of wheat is starch, how many lbs. of starch in 20 bus.? 

 3. It requires 500 lbs. of water to produce one pound of hay. 

 How much water is required to produce a ton of hay? 



Exercises: 



1. If possible, find some large rocks and note the cracks in them, 

 and the little depressions where there is a small accumulation of soil. 

 Note the growth of moss or other forms of plant life. Write out a 

 description of what you have seen. 



2. Burn some dry plants and note that a small part of them is 

 left. We call it ashes. It is mineral matter. The part that disap- 

 pears in the burning process as smoke and gas is the vegetable matter. 



3. Get samples of gravel, sand and clay. Put a very small amount 

 of each on a piece of white paper. Notice how they look and feel. 



