ECONOMIC VALUE OF FUMIGATION 



223 



infectant for nursery stock. The writer being aware 

 of the use of this gas in California upon nursery stock 

 as early as 1890, wrote Alexander Craw, State Ento- 

 mologist and Quarantine Officer of California, who re- 

 plies as follows : 



First use upon nursery stock. "Fumigation by 



FIG. 83 SPRAYED ORANGE TREE 



Orchard of W. F. Stearns, near National City, California 

 (Photograph by H. R. Fitch, July 18, 1901) 



hydrocyanic acid gas was practiced in Southern 

 California for the disinfection of nursery stock as 

 early as 1889-90. Upon page 479 of the ' Report of 

 the California State Board of Horticulture for 1890' 

 the following reference to fumigating nursery trees is 

 made : ' The Commission has used the utmost vigi- 



