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general city use. Probably the largest elm tree in America, the Dex- 

 ter elm at Medford, Mass., has been successfully and economically 

 sprayed by the Gypsy Moth Commission. It is necessary to have 

 especial apparatus constructed, and it is equally necessary to have the 

 work done by men who are accustomed to it or at least are good climb- 

 ers. The first successful work of this kind was probably that done by 

 Prof. John B. Smith, on the campus of Rutgers College. He had a 

 strong barrel pump, and carried the nozzle at the end of a long rubber 

 tube, with a bamboo extension pole, up into the center of the trees by 

 climbing a ladder to the main crotch. From this point the spray was 

 thrown in all directions, and the tree was thoroughly coated with the 

 mixture in a minimum of time. 



The Gypsy Moth Commission, in their earlier spraying work, sent 

 their large tank carts through the streets, stopping at each tree and 

 sending one or more men with hose and extension poles into it, thus 

 covering hundreds of large trees in a single day. If steam sprayers 

 are used (and the town or city iire engines can be and have been used 

 to excellent advantage in this way), the necessity for climbing the 

 trees may be largely avoided. By means of multiple-discharge hose 

 both sides of a tree, or even of two trees, may be sprayed at once, 

 and the extent of territory that may be covered in a day is surprising. 

 The elm trees in a small park may be treated economically and with- 

 out much difficulty by two or three men with a handcart tank. This 

 method has been adopted on the large grounds of the Department of 

 Agriculture with absolute success. 



The writer's experience at Washington leads to the conclusion that 

 it is important to spray trees once just after the buds have burst. 

 This spraying is directed against the overwintered beetles. If a large 

 proportion of these beetles can be destroyed by poisoning the leaves 

 which they eat, not only will a great deal of leaf perforation by the 

 beetles themselves be prevented, but the number of eggs laid will be 

 very greatly lessened. A second spraying should be conducted two 

 weeks later. This is directed against the larvae, the majority of which 

 will perhaps have hatched by that time or soon after. A third spray- 

 ing, and e?en a fourth, or under exceptional circumstances a fifth, 

 maj be required if it is considered necessary to keep the trees fresh 

 and green, and particularly if the earlier sprayings have been followed 

 by rains, as is apt to be the case in the earlier part of the season. In 

 Bridgeport, Conn., where only a part of the trees are sprayed and 

 these by private enterprise, an even greater number of operations 

 have been found desirable. Three thorough sprayings of all the trees 

 in a given precinct will probably be as much as will be required, 

 especially if this be done year after year and some pains be taken to 

 destroy such of the larvae as may successfully develop and descend for 

 transformation. Even two sprayings, covering all the elms of a city 

 or town, will be well worth the expense. 



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