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over quickly when on the trees. The resin oil specified saponifies 

 in 4-10 minutes ; oils that saponify more rapidly are not so satis- 

 factory in use. If the commercial hydrated lime cannot be obtained, 

 ordinary rock or quicklime can be used ; it must be slaked with just 

 enough water to make the resultant product a dry powder or hj'drated 

 lime. This should be passed through a sieve having 14 meshes to 

 an inch ; a coarser mesh should not be used. 



The material was mi.xed in a 25-gallon soap kettle with an arrange- 

 ment of stirring paddles ; the kettle was provided with a steanirjacket, 

 but usually no heat was required. As a rule, mixing should be done 

 at 60-75° F. The construction of this plant is fully shown in a 

 sectional figure. 



The banding material was made in large quantities as follows ; 

 one part by weight of hard coal-tar pitch was placed in the kettle ; 

 one part by weight of coal-tar neutral oil was added ; heat was then 

 applied until the pitch had melted and thoroughly mixed with the oil ; 

 the kettle was then removed and two more parts by weight of coal-tar 

 neutral oil were added and everything was thoroughly mixed. This 

 product, known as " pitch neutral oil mixture," could be poured and 

 worked after cooling, and formed a stock mixture. 



To prepare the banding material, 18 lb. of the stock mixture and 

 70 lb. of the coal-tar neutral oil were placed in the kettle and stirred. 

 In a few moments 12 lb. of hydrated lime was added slowly. When 

 the contents had become of a uniform consistency 50 lb. of resin oil 

 was added and mixed for a few minutes, or until the contents began 

 to thicken. Then 20 lb. of coal-tar neutral oil was added, and the 

 contents were thoroughly mixed. The stirring was then stopped, 

 and the material poured into containers. In 2-3 days it had set to 

 a semi-solid state. In cold weather it is slightly stiff, but it can be 

 applied easily at 35° F. At higher temperatures it works very 

 easily. 



The above product is suited to New England or a similar climate. 

 For a warmer climate it may, if required, be made harder bj' slightly 

 increasing the amount of resin oil and lime. In a much colder climate 

 it may be made softer by the addition of a little more coal-tar 

 neutral oil. 



If an excess of lime is added to bring the material up to the desired 

 consistency, the product will have a more or less granular appearance 

 and will soon become devoid of the most desirable oily surface when 

 on the trees. 



If the viscosity of the resin varies, the amount used must be altered. 

 A reduction of 4 lb. resin oil should be made to every 15 points increase 

 in viscosity. Each 4 lb. reduction of resin oil entails a 4 lb. addition 

 of coal-tar neutral oil. Half this addition is made to the amount 

 first added (70 lb. in the formula), and half to the amount last added 

 (20 lb.) to the mixer. 



The material is most conveniently applied by a special " gun," 

 a full description of which is given. It consists of a tin cylinder with 

 a plunger and flat nozzle, delivering a band f f by /^r inch, which 

 is suitable where the infestation is not too severe and is the most 

 satisfactory under average conditions. 



The bands ma}' be placed low down or 5-8 feet high. In the first 

 case small caterpillars will not be able to climb up into a position 

 from which they may be dislodged and dispersed by the wind. In 

 the second case cattle and other animals are unable to rub against 

 them. If regular or frequent care cannot be given to the bands, it 



