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Spraying for shade tree insects should be thorough. A mist spray 

 at high pressure should be employed for as high as the extension will reach ; 

 and for the higher portions the solid stream is necessary. The latter uses 

 the spray mixtures very rapidly and should be employed with discretion. 

 It is, of course, quite necessary to understand the habits of the insects 

 to be controlled and to make the sprays at the proper time. 



Hand picking is effective to a very limited extent. The tents of 

 the American Tent Caterpillar can be removed by means of tree-trimmers 

 or torches; egg-mases of the tent-caterpillars and the tussock moths can 

 be removed by hand at times with profit; and the larger caterpillars, which 

 rarely occur in great numbers, can sometimes be removed from low foliage 

 by hand more cheaply and effectively than in any other way. 



The Destruction of larger Borers. — When living trees become 

 infested with large boring grubs or caterpillars it is necessary to kill the 

 borers in their tunnels with the least possible injury to the trees. When 

 the borers are near the surface it is often possible to cut them out with a 

 knife or chisel without much injury to the wood. A wire thrust into the 

 borings can sometimes be used effectively. It is usually possible to kill 

 the grubs by injecting carbon bisulphide or benzine into the openings. 

 The fluid should be injected with a syringe or oiling-can and the opening 

 should be immediately closed with soap or putty. After several hours 

 the holes should be opened, the grubs removed if easily reached, decaying 

 wood cut away, the holes thoroughly syringed with strong lime sulphur 

 or copper sulphate or with a solution of bichloride of mercury, and finally 

 filled with cement. The carbon bisulphide or the benzine should be in 

 jected into the flatter holes from which sap and borings have been oozing 

 and which evidently lead to the tunnels of living larvae. It is useless 

 to inject insecticides into the exit-holes from which the adults have escaped, 

 although such holes should be disinfected and filled with putty or cement. 



Banding the trunks of deciduous trees to prevent infestation 

 from wandering hordes of tent caterpillars or from the wingless females 

 of the cankerworms is often a necessary precaution. The most effective 

 method is to make a complete girdle about the trunk with a sticky sub- 

 stance over which the insects cannot crawl. The adhesive should be 

 applied in a band about four inches wide to stout paper tacked or tied 

 about the trunk five or six feet from the ground. If the bark is eneven 

 cotton should be placed beneath the paper to prevent the insects passing 

 beneath. One of the best adhesives for banding is made by boiling resin 

 and castor oil in equal parts and thoroughly mixing. The well-known 

 preparation "Tree tanglefoot" is widely used for this purpose, and can 

 be obtained from dealers in insecticides. 



