72 ALFALFA 



and grain, allowing for each of these occupying one- 

 third of the farm every year; that is to say, the place 

 is given over to these three crops, but they are 

 alternated each year. 



The following summary from a bulletin on ' ' Alfalfa 

 as a Fertilizer, ' ' by the Wyoming Experiment Station, 

 is suggestive if not conclusive: 



"The most important fertilizer, for the arid or 

 semi-arid region, is nitrogen. 



"Some plants, of which alfalfa is one, have the 

 power to fix in the soil the free nitrogen of the air. 

 They do this by means of micro-organisms which form 

 bunches or nodules on the roots. 



" Therefore, growing alfalfa on the land increases 

 the quantity of nitrogen in the soil and pradlically 

 solves the fertilizer problem for the West. 



' ' Alfalfa also improves the soil tilth by shading 

 the ground and adding humus by decay of its large, 

 deep-growing roots. 



" Growing alfalfa destroys weeds. 



"The value of alfalfa harvested from one-half 

 acre of land for five years at Laramie was about $50 

 more than the cost of producing it. 



" The value of potatoes and grain from an adjoin- 

 ing half-acre for five years was about $44 more than 

 the cost of producing at local prices. 



"When alfalfa land was plowed and planted to 

 wheat it produced $8 to $1 2 more value in wheat per 

 acre than the land which had grown potatoes and 

 grain before. 



"When alfalfa land was plowed and planted to 

 oats, it produced $i6 worth of grain more than land 

 which had grown potatoes and grain before. 



