104 ALFALFA FARMING IN AMERICA. 



Deficiency in Soil. -Curiously enough there are 

 many- well drained soils in the eastern part of the 

 United States that are admirably adapted to being 

 penetrated by alfalfa roots, yet on which alfalfa does 

 not naturally grow well, if at all. Such soils often 

 are loose, pervious, easily penetrated by roots. They 

 may be of clayey lo<am order, or have sandy or 

 gravelly nature. On them perhaps grow chestnut 

 trees. Chestnut soils ought usually to be good al- 

 falfa soils. Naturally they are not. By right treat- 

 ment they may be made good. The clue to their 

 reclamation is lime. 



Soil a Living Thing. A. soil is a living, drink- 

 ing, breathing thing. If it is truly alive it has in it 

 much air, sufficient water, but that held in suspen- 

 sion 'as film water only in the earth, not in satura- 

 tion. That is, there is a film of water about each 

 little grain of sand, between each two grains of soil, 

 and between the layers of water is air. The living 

 soil has in it humus, vegetable matter, in greater or 

 less amounts. It has in it bacteria in immense num- 

 bers. It is alive with bacteria. These bacteria are 

 of various kinds and orders. Some are engaged in 

 destroying humus. They break it down and from 

 the nitrogen in the humus make soluble nitrates. 

 These the plants can absorb through their rootlets. 

 Some of these bacteria are able to assimilate the 

 free nitrogen of the air and make it available for 

 plants growing with roots in that soil. These bac- 

 teria exist in all soils probably where there is 

 plenty of humus decaying. Other bacteria there are 



