YIELD OF ALFALFA. 



I desire to raise no hopes in the reader's mind 

 that can not be realized and I have thus sought to be 

 moderate in my estimates of what alfalfa would 

 yield per acre. It is a most interesting question to 

 study, the possible yield of alfalfa in various soils. 

 In California, with a very long growing season, we 

 are assured that as much as 12 tons of dry hay has 

 been harvested per acre. This of course was done 

 by irrigation in a soil peculiarly well fitted to alfalfa 

 growing. It may fairly be taken as the extreme 

 limit of possibilities. There are alfalfa fields that 

 because of unfitness of soil, do not yield more than 

 one or two tons per acre. What then, ought we to 

 get? 



Moisture the Limiting Factor. — Given plant food 

 in the soil and proper bacterial relations alfalfa 

 ought to grow about as well in one place as in an- 

 other. The limiting factor in almost all crop pro- 

 duction is water. Alfalfa usually does not have 

 moisture enough to make a maximum crop. Even 

 on wet soils, and chiefly on undrained soils, it does 

 not have water eno'Ugh. That is because its roots do 

 not werk in undrained soils so it must forage only 

 on the surface. All plants drink their food ; they do 

 not eat as animals do. Given water enough in a deep 

 pervious soil that the roots can use, and plant food, 

 alfalfa will do its best. 



(S49) 



