

HOW TO DETECT OUTBREAKS OF 



INSECTS AND SAVE THE 

 GRAIN CROPS 



W. R. WALTON 



Entomologist in Charge of Cereal and Forage Insect Investigations 



A billbug, much enlarged 



FARMERS' BULLETIN 835 

 UNITED STATES DEPARTMENT OF AGRICULTURE 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



June, 1917 



Additional copies of this bulletin may be obtained free from the 

 Division of Publications, U. S. Department of Agriculture 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1917 



