FORAGE CROPS 117 



In the small tubercles to be seen on the roots of clover, 

 alfalfa, soy-beans or cow-peas are millions of bacteria, each 

 able in the process of its own growth to take nitrogen from 

 the air, change it into the form needed by growing 

 plants, and leave it in the soil for the next crop. In this 

 way the legume is able not only to secure its own growth, 

 but to leave the soil richer through the action of its bac- 

 teria friends. The raising of legumes is therefore one of 

 the best and most economical ways of enriching the soil. So 

 important is the group of legumes that a separate chapter 

 will be given the most important ones. 



TOPICS FOR INVESTIGATION 



1. What are the chief grasses used for pasturage in 

 your neighborhood? For hay? For lawns? 



2. What are the principal legumes cultivated in your 

 vicinity? Which are annuals? Which are perennials? 



3. Make a collection of the principal grasses found on 

 your father's farm. Study their method of growth. Com- 

 pare stems, leaves, roots, and method of seed bearing. 



4. Make a similar collection and study of the com- 

 mon legumes. 



5. Secure the roots of clover, of alfalfa, of peas, beans 

 and any other available legumes. Make a study of the tu- 

 bercles, comparing size and number. The bacteria are too 

 small to be seen except with a powerful microscope. The 

 tubercles are most plentiful in the early part of the grow- 

 ing season. 



6. Illustrate how a bookkeeping record can be kept of 

 the various types of forage crops, such as alfalfa, cow- 

 peas, red and crimson clover, blue-grass, etc. 



7. Make a study of the map, locate the principal for- 

 age territories, and indicate the various types of grasses 

 and forage crops that have been produced in the different 

 sections. Indicate in each state the acreage allotted to 

 each type of forage. 



8. Indicate what kind of stock thrives best on certain 

 forage crops, and tell why. 



