SPRAYING FOR THE CITRUS MEALY BUG 247 



infected orchard. The resuUs were httle better than what was obtained by 

 a single dose and one hour exposure. In many cases only about 50 per cent of 

 the female bugs were killed, while the percentage of the eggs remained 

 unknown. The cost of the single time for an average lemon tree, including 

 labor and tents, was nearly $1.50. 



Believing in a three hour exposure and a triple dosage, an owner of a 

 badly infested orchard, wished his orchard so treated. After two nights' 

 work a halt was called to await an inspection so as to get some idea of the 

 results obtained. An inspection followed which showed as many as 40 in- 

 dividual mealy bugs on a single tree. The work was stopped and a closer 

 inspection made which resulted in the work being dropped. The cost per 

 tree was near $2.25 and the results very poor. 



It was after this and other work, that my attention was turned to some 

 other means of combating the mealy bug, than by fumigation or the use of 

 the already promising parasites which were working very slowly. To sprays 

 I turned first, believing that a mixture could be found which would do tiie 

 work. Sprays seemed advisable for the following reasons. 



1. At most times of the year the mealy bugs are scattered over the 

 tree in the most exposed manner. Only during the winter months are they 

 massed and more or less protected by their numbers. 



2. The only protection afforded to these soft-bodied insects is a thin, 

 white, waxy covering. The requisite for a successful spray would be the 

 power of penetrating and dissolving this waxy coat. 



3. A spray which would kill the adults would exterminate all the eggs 

 on the tree at the time of spraying. 



4. Weather conditions are more favorable for spraying in this country 

 than for fumigation, because of damp nights, east winds, etc. 



With these things in mind, work was begun with both wet and dry 

 sprays. The section chosen was an average-aged lemon orchard very badly 

 infested with mealy bug — a section of about two acres, and where parasites 

 had not been introduced. 



The work was carried on during the months of January, February, and 

 March, when the trees were more or less dormant, and when the mealy bugs 

 and eggs were massed in great clusters on the trunks, limbs, leaves, and fruit 

 of the trees. The results were so good that beginning July 1st, over 100 

 acres will be sprayed and steps taken to make a general cleaning up of the 

 entire mealy bug district. Of course there are many things yet to be perfected 

 in regard to the time for spraying and the manner of application, but with 

 an efficient spray to work with, these details will develop only with experience 

 and time. 



Even the following experiments are in no wise perfected, but shall serve 

 to show simply how far the work has been carried to the present time. 

 The work is only begun, and from time to time, I shall be able to furnish 

 a great deal more material upon this subject. 



In all the spraying experiments, the one dominant aim was to find a 

 solution which would effectually dissolve the waxy covering of the scale body 



