ELM LEAF BEETLE AND WHITE-MARKED TUSSOCK MOTH 13 



Communities usually fail to realize that in the elm leaf beetle 

 we are dealing with an insect extremely sensitive to poison 

 and one which will feed upon sprayed leaves only when no others 

 are available. Its senses are so keen that it can detect poison 

 hardly visible with a powerful hand lens. Under such conditions 

 one may readily see how easy it is to secure indifferent results. 

 Spraying trees is a disagreeable, hazardous occupation, and in 

 order to secure the best returns, it is necessary to make the com- 

 pensation such as to result in a keen competition for the position 

 of nozzleman. The application of business principles would justify 

 larger municipalities placing this work in the hands of one who 

 understood at least the rudiments involved (a skilled landscape 

 gardener or forester would be even better) and giving him au- 

 thority to insist upon any reasonable standards in methods and 

 operation. Such a person could reasonably be expected, if pro- 

 vided with sufficient funds, to keep the foliage of elms practically 

 intact throughout the season, even in sections where the elm 

 leaf beetle was excessively abundant or upon trees adjacent to 

 those badly injured by the pest. Many trees were badly injured 

 last year because there was so much difficulty in securing men 

 who would do thorough work, a prime essential in an under- 

 taking of this kind. 



The effective spraying season extends from early to middle 

 May till nearly the latter part of June, a total of approximately 

 six weeks. Making allowances for interruptions by rain, we 

 can hardly expect more than thirty full working days during 

 this period. A power spraying outfit of the usual type and 

 provided with two lines of hose can spray thoroughly, perhaps 

 fifty trees a day or a maximum of 1500 during the season as 

 restricted above, much depending upon the size and location of the 

 trees as well as the efficiency of the men in charge. 



The cost of thorough spraying is not excessive. It may be esti- 

 mated at about 50 cents a tree or only 10-20 cents a tree if all 

 the work be done from the ground with a high power outfit, in 

 each case making no allowance for the cost of apparatus. A 

 power spraying outfit adapted to shade tree work can hardly 

 be obtained for less than $275 to $500, and in case of the high 

 pressure outfits, may easily amount to more than double the 

 latter sum. There should be plenty of power, an abundance of 

 hose and good ladders unless it is planned to do all the work 

 from the ground. This work can be done with a powerful hand 

 pump at a greater cost for operation though the initial expense 



