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practice to employ long poles for this latter purpose, 

 simply attaching the nozzle to one end by wrapping it 

 with twine. A large bamboo rod with the septa burned 

 out to permit the hose to be passed up through it, has 

 been recommended for this same purpose and has ad- 

 vantages of lightness and convenience in its favor. For 

 exceptionally tall trees it is necessary to employ besides, 

 a ladder, and occasionally it may be necessary to throw 

 a solid stream of the fluids used, trusting to the friction 

 against the atmosphere to break it into a spray. Some 

 of the nozzles sold for this work are so constructed that 

 the cap concerned in producing the spray can be re- 

 moved, thus permitting a single stream to issue, which is 

 thrown to a greater distance. The spray itself may be 

 thrown horizontally by means of some of these pumps 

 and nozzles a distance of 25 feet. Thrown vertically, or 

 nearly so, it would not go so far, henoe the occasional 

 necessity of the other method for reaching the leaves. 



The quantity of poison to be used varies with the kind 

 of trees to be sprayed. For apple trees it is customary 

 to use 1 pound of either London purple or Paris green 

 in from 160 to 200 gallons of water. We have used the 

 former proportion (1 lb. to 160 gallons) at the Experi- 

 ment Station, with little or no injury to the leaves. To 

 avoid the danger of damaging the leaves it is well to ex- 

 periment on a branch, or at most a single tree, before 

 doing more extensive spraying, remembering however, 

 that the poisons may not show their destructive effects 

 on either leaves or insects until several days have elapsed. 

 These poisons lose none of their effectiveness as insecti- 

 cides when mixed with wheat flour, and the addition of 

 the flour renders the mixture more adhesive and less in- 

 jurious to the leaves, hence it is well to use the two in 

 combination where possible. For spraying the leaves of 

 elm trees Dr. C. V. Riley recommends, after some exper- 



