38 HYDROCYANIC-ACID GAS FUMIGATION IN CALIFORNIA. 



pullers seldom get more than one or two trees ahead of the cart, 

 and thus all trees receive the same length of exposure. The work of 

 the men who dose the trees is easier than where the heavy trays are 

 used. Another decided advantage is that the orchardist can at any 

 time determine what character of treatment is being given his trees 

 and see that the work is properly carried out. In the past many 

 persons have been prone to look upon fumigation as a process that 

 is complex and more or less mysterious. In some cases fumigators 

 of years' experience have encouraged this widely prevailing opinion, 

 so that they might themselves be looked upon as experts in a prac- 

 tice difficult to understand and only capable of being successfully 

 performed by men of long experience and special qualifications. 

 This is, of course, erroneous. The improved system outlined in 

 these pages shows how simple the practice of fumigation may be 

 made. Careful men who have never before heard of fumigation 

 can begin the practice of this system and are competent, after a 

 few hours of instruction, to secure even better results than were to 

 be expected from the most expert fumigator in California under the 

 old method. This system reduces fumigation to a matter of simple 

 mechanical operation, entirely intelligible to the average man, 

 wherein the operator, to obtain the best results, is required merely 

 to proceed according to the formulas and directions given. Hence, 

 orchardists are enabled to own their own outfits and carry on their 

 work after the most economical as well as successful manner. Owner- 

 ship of tents is to be advised for several reasons, which are fully 

 explained elsewhere in this bulletin. Fumigation then can be con- 

 ducted at the most opportune time, good and careful work is assured, 

 while the expense is at a minimum. An orchardist owning his own 

 tents can keep his fruit clean at all times, which otherwise might be 

 impossible, because the number of fumigation outfits in southern 

 California at the present time is insufficient to cope properly with 

 the situation. 



EXPERIENCE WITH THIS SYSTEM. 



The introduction of this improved system was made with two 

 outfits of the Whittier Citrus Association, at Whittier, Cal., during 

 the latter part of July, 1908, using dosage schedule No. 1 for the 

 purple scale. On August 15 a demonstration was made before a 

 meeting of fruit growers and fumigators in Los Angeles and pro- 

 voked deep interest. The very successful work against the purple 

 scale at Whittier had begun to be evident by this time and led to 

 the prompt adoption of the system by the orchardists thereabout. 

 Growers from other localities, inquiring into the experience with 

 the recent innovation at Whittier, commenced to sanction its adop- 

 tion in their respective districts, so that by the end of the fumiga- 



