6S4 



Handbook of Nature-Sttidy 



Alfalfa is so dependent on its little underground partners, that it 



cannot grow without them; and so the farmer plants, with the alfalfa 



seed, some of the soil from an old alfalfa field, which is rich in these bac- 

 teria. On a farm I know, the bacterial 

 soil gave out before all of the seed was 

 planted ; and when the crop was ready 

 to cut it was easy to see just where the 

 seed without the inoculated soil had 

 been planted, for the plants that grew 

 there were small and poor, while the 

 remainder of the field showed a luxu- 

 rious growth. 



It is because of the great quantity of 

 nitrogen absorbed from the air through 

 the bacteria on its roots that the alfalfa 

 is such a valuable fodder; for it con- 

 tains the nitrogen which otherwise 

 would have to be furnished to cattle in 

 expensive grain or cctton-seed meal. 

 The farmer who gives his stock alfalfa 

 does not need to pay such large bills 

 tor grain. Other plants belonging to 

 the same family as the clovers — like 

 the vetches and cow-peas — also have 

 bacteria on their roots. But each 

 species of legume has its own species of 

 bacteria; although in some cases soil 

 inoculated with bacteria from one 

 species of legume will grow it on roots 

 of another species. Thus, the bacteria 

 on the roots of sweet clover will grow 

 on the roots of alfalfa and many farmers 

 use the soil inoculated by sweet clover 

 to start their alfalfa crops. 

 In addition to the enriching of the soil, clover roots, which penetrate 



very deeply, protect land from being washed away by freshets and heavy 



rains ; and since clover foliage makes a thick 



carpet over the surface of the soil, it prC' 



vents evaporation and thus keeps the soil 



moist. Crimson clover is used extensively 



as a cover crop; it is sowed in the fall, 



especially where clean culture is practiced 



in orchards, and spreads its leaves above 



and its roots within the soil, keeping out 



weeds and protecting the land. In the 



spring it may be plowed under, and thus 



add again to the fertility. This is also an 



aesthetic crop, for a field of crimson clover 



in bloom is one of the most beautiful sights 



in our rural landscape. 



Red clover has such deep florets that, 



of all our beeS; only the bumblebees have Red cljver blossom. 



Alfalfa in leaf and blossom. 



