118 BOARD OF AGRICULTURE. [Pub. Doc. 



Doubtless you have before heard the praises of alfalfa sung 

 and now you ask, '^ Is it a pr^icticable crop for the Massa- 

 chusetts farmer ? Can I grow it ? I live on the sandy river 

 bottoms, can I grow it there ? I live on the clay hills, can 

 I grow it there also ? " 



To this I reply, " Yes, alfalfa will grow profitably on 

 every farm in Massachusetts. There are no exceptions, so 

 long as the drainage can be made good. Let us consider the 

 requirements of the alfalfa plant. It makes its growth 

 mainly by the aid of the bacteria that inhabit its roots. 

 These bacteria live upon the air that is in the soil. They 

 have the power to take nitrogen from the air, digest it, and 

 make available the nitrogen for feeding the plants. The 

 lesson is plain. Alfalfa must not be in a waterlogged soil. 

 There must be air in the soil as well as moisture. Drainage, 

 then, is the first requisite of an alfalfa field. 



Lime is the second requisite. All the natural alfalfa- 

 growing regions of the world have soils strongly impregnated 

 with limestone. Idaho alfalfa fields have about 4 per cent 

 of limestone in them. Colorado soils have at least as much. 



IvTebraska soils have from IVo to 4 per cent of carbonate 

 of lime. In Onondaga County, 'N. Y., where alfalfa gi*ows 

 so easily and so well, the soil is rich in lime; the rocks 

 underlying the region are of limestone. Successful alfalfa 

 growing is a mere matter of the chemistry of the soil, — that 

 and the attention to a few easily learned likings of the 

 plant. 



When it comes to liming soils for alfalfa growing, one 

 needs to forget most of what he has read of the functions of 

 lime in the soil, because alfalfa uses lime in a different man- 

 ner and for a different purpose from most other plants. The 

 lime is for the bacteria, to enable them to gather the nitrogen 

 from the air. Just how this is done we do not know, but 

 this is sure : with abundant lime in the soil we find abundant 

 and active nitrifying alfalfa bacteria, while without the 

 lime we find few bacteria and these inactive. Markedly 

 healthy alfalfa is always found to be on soils filled with lime- 

 stone. To the alfalfa plant limestone in the soil is far more 

 important and essential than manure. 



