9. HOW LEGUMES HELP THE FARMER. 



Illustrative material: Plant not over one fourth of an inch 

 deep in moist garden soil in a fruit jar, two or three hundred 

 seeds of common red clover. Screw on the cap loosely, and 

 place the jar in a warm place.. When the plants are well grown, 

 fill the jar with water and let it stand until the soil is thoroughly 

 soaked; then gently draw the plants out so as to injure the roots 

 as little as possible. Pass the plants about the class, and let the 

 pupils find the swellings on the roots. 



Clover a Fertilizer. Nearly every boy and girl knows 

 the clover plant, with its three (rarely four) oval leaflets 

 and its pretty red or white blossoms. They know, too, 

 that all farm animals are fond of clover, both fresh and 

 made into hay. The intelligent farmer knows that the 

 clover plant is valuable not only for pasture and hay, but 

 also as a fertilizer of the soil. 



Clover Takes Nitrogen from the Air. Figure 18 

 shows a young clover plant. By looking closely at the 

 picture, we may see little swellings or knobs on the 

 larger roots. While these knobs, or tubercles, as they 

 are called, are not so pretty as the leaf or the flower, they 

 are full of interest to the educated farmer, for they serve 

 as minute laboratories for the manufacture of nitric acid 

 in the soil, and thus they supply the plant with nitrogen, 

 the most important kind of plant food. 



Nitrates. The housekeeper can not make bread out of 

 unground wheat, however much she may have of it. The 

 grain must first be ground and sifted, arid then the fine 



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