U. S. DEPARTMENT OF AGRICULTURE, 

 BUREAU OF ENTOMOLOGY— BULLETIN No. 90. 



L. O. HOWARD, Entomologist and Chief of Bureau. 



HYDROCYANIC-ACID GAS FUMIGATION 

 IN CALIFORNIA. 



I. FUMIGATION OF CITRUS TREES. 



By R. S. WOGLUM/M. S. A., Special Field Agen* 



II. THE VALUE OF SODIUM CYANID FOR FUMIGATION PURPOSES 



By R. S. WOGLUM, M. S. A., Special Field Agent. 



III. CHEMISTRY OF FUMIGATION WITH HYDROCYANIC-ACID GAS. 



By C. C. McDONNELL, Chief , Insecticide and Fungicide Laboratory 

 Miscellaneous Division, Bureau of Chemistry. 



government" printing office. 



/ 



Z-$4 IS'S' 



1912. 



