hrevicauda) as the species to which credit shoukl be given, and prob- 

 ably much of the work is done while the grain is in shock. 



Rotation of crops is advantageous, because it necessitates the 

 migration of adults from one field to another, and if this takes place in 

 storni}^ weather or during high winds, many of the migrants will be 

 killed or blow^n astray. It is easily seen that where infested straw is 

 applied to a new field prior to sowing to wheat, this migration of 

 adults would not be made necessary. 



The sowing of early ripening varieties is also beneficial. 



Approved : 



James Wilson, 



Secretary of Agriculture. 

 Washington, D. C, July 16, 1908. 



[Cir. GG] 



o 



