SPRAYING FOR THE CITRUS MEALY BUG 



E. O. ESSIG 



horticulTurai, commissioner 

 of ventura county, cawfornia 



From time to time articles have appeared with reference to handling 

 the citrus mealy bug by fumigation and parasites. Fumigation was certainly 

 given an excellent test in this county, and while, through persistent en- 

 deavor, it has accomplished much good, yet to the average orchardist this 

 method is beyond reach. The best work was done in a ten-acre lemon orchard 

 belonging to the Teague-McKevett Co. just east of Santa Paula. Adjoining 

 the old ten-acre orchard, this company planted some 240 acres of young 

 lemon trees, and when the mealy bug was found to exist in tlie old orchard, 

 the owners sought to exterminate it at any cost to prevent its spreading 

 into the young grove. Former County Commissioner P. E. Smith started 

 this work during the fall of 1908 and it had been carried on until the present 

 time. The first tree-to-tree inspection showed 200 trees infested with mealy 

 bug. After this inspection the entire orchard was fumigated, the dose used 

 being in accordance with Woglum's Dosage Schedule No. 1. A second in- 

 spection some two months later showed 75 trees still infested and all these 

 trees as well as those adjacent to them were fumigated as at first. 



The third inspection, not being so careful, showed only a few trees 

 infested and these were fumigated with a dosage double that used in Dosage 

 Schedule No. 1. The results of this fumigation looked very favorable. 



Three months later a very thorough inspection was made, the time re- 

 quired for the ten acres being six weeks. This inspection showed over 100 

 trees infested, some of them with eggs only, while others apparently supported 

 only a single individual. The fourth fumigation was carried on differently 

 from any work recorded on the mealy bug. Instead of a double dose being 

 given at once, as was used in the third fumigation, a single dose was given 

 as is the usual custom. After one hour exposure this dose was repeated, 

 thus making the dosage double that outlined in Woglum's Dosage Schedule 

 No. 1 and the exposure two hours. It was believed that this would surely 

 get all of the insects which the one hour exposure and one dose did not kill. 

 The results were indeed very satisfactory. So much so that the fifth in- 

 spection, which was even more careful than the fourth, revealed only four trees 

 slightly infested. These trees were fumigated with the same system of dosage 

 as soon as they were found by the inspector. A later inspection has revealed 

 no mealy bugs, but only after some time, yet, can we make sure of this. 

 The work shows that the reduction of the pest is exceedingly great and that 

 through repeated fumigations the pest can he practically exterminated in 

 an orchard, but the cost would make it absolutely prohibitive in a large 

 orchard, which was badly infested in all parts. To demonstrate this the 

 double dosage and double exposure system was carried into a very Ijadly 



