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■will not keep as well as the emulsion made with hard soap. Their 

 killing properties are equally as good and they do not damage the 

 foliage. Kerosene emulsion is an invaluable remedy against 

 nearly all plant and bark lice and for this purpose it should be 

 applied as a spray. 



Raupenleim, Etc. 



Another class of insecticides, or perhaps more properly "insect- 

 traps," includes the various mixtures for banding trees to prevent 

 the ascent of injurious insects. Chief among these are coal tar, 

 printers' ink and the German Raupenleim ("insect lime"), or, 

 correctly, caterpillar-glue. When gas tar, printers' ink or a 

 mixture of the two are used a tight-fitting band of tarred sheathing 

 paper should be first tacked around the tree and the substance 

 spread on the band, thus avoiding injury to the bark. With 

 Raupenleim as ordinarily used there is not much danger of injury. 

 Before applying it the trunks of the trees should be scraped 

 smooth at the point on which the band is to be placed. The sub- 

 stance is a German preparation whose composition is a jealously 

 guarded secret. It has been used by the State Board of Agricul- 

 ture with fairly good success against the gypsy moth for two 

 seasons, but as it was not found to meet all the requirements of 

 the work its use was discontinued. It is apparently the product 

 of some mineral oil. Prof. John B. Smith, entomologist to the 

 New Jersey Agricultural Experiment Station, who has kindly 

 placed at my disposal the notes made on a series of experiments 

 with Ibis substance, finds that aside from its value in stopping the 

 passage of insects up and down trees, it has also proved an excel- 

 lent means of preventing borers from laying their eggs on tree 

 trunks. Against the sinuate pear borer, which has caused con- 

 siderable damage to orchards in New Jersey, Professor Smith 

 found it to be a most successful preventive when properly applied. 

 For this purpose it was applied in a coat three-sixteenths of an 

 inch thick over the whole trunk of the tree as far as the lower 

 branches. 



For use against the canker-worms apply the Raupenleim in a 

 band one-fourth of an inch thick and three to four inches wide 

 around the tree. The Raupenleim may be put on with a paddle and 

 spread with a stiff brush. The bands should be put on the trees 

 about October 1 and freshened the following spring. If left on 

 during the summer these bands will prevent such trees as have 

 been properly cleaned of the eggs of the tussock moth from 

 becoming infested with the caterpillars of this insect. Raupenleim 

 may be purchased in the market at from ten to fifteen cents per 

 pound, according to the quantity desired. 



