EXPERIMENT STATION BULLETINS. 303 



the nitrogen content of the soil after it has been grown for several years 

 in a field as it does during the first two or three jears after seeding. 

 It is, therefore, not advisable to leave one field seeded for an indefinite 

 period of years, or as long as it produces satisfactorily as is commonly 

 done, but to seed a new field which needs building up and to plow up 

 the old field which should be in condition to produce very satisfactory 

 yields of corn and other crops. 



This would necessitate the inclusion of alfalfa in the rotation of 

 crops and bring about other radical changes in the rotations as com- 



Fig. IX. A field of alfalfa and orchard grass on the college farm, which has produced an average 

 yield of.6 tons per acre during the past 5 years. Orchard grass is one of the best grasses for mixing 

 with alfalfa for pasture or to produce a hay for horses. 



monly practiced throughout the state. The rotation of crops suited to 

 a particular farm will depend upon the type of soil and the adaptability 

 of the various crops to the same ; the type of farming engaged in ; the 

 markets and other local factors. No detailed plans of rotations of 

 crops are presented in this bulletin but the following suggestions are 

 offered as being worthy of consideration : The best plan of carrying 

 out a definite rotation including the alfalfa, is the short rotation of 

 annual crops inside the long or complete rotation, that is, the alfalfa 

 is left seeded in one field for a short period of years and the remainder 

 of the farm devoted to the short rotation. After a few years the old 

 field of alfalfa is plowed up and devoted to the short rotation and 

 alfalfa seeded in a new field. 



