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the United States Agricultural report for 1883, pp. 167-169 there 

 is given a detailed account of the methods employed at Washing- 

 ton to destroy this beetle and the results obtained. These were, in 

 briefest statement: "From midsummer imtil autumn the un- 

 poisoned hall (of a grove of elms) remained denuded of foliage 

 while the poisoned half retained its verdure." As has been stated 

 the beetle w^as imported with the European elm, but it has grad- 

 ually extended its operations to the American elm. One of the 

 most helpful accounts of operations against this beetle which I 

 have come across was published by Prof. J. B. Saiith, in Garden 

 and Forest^ Juiie 19, 1889, and as the suggestions therein given 

 apply almost or quite as well to any other leaf-eating insect and to 

 any other tree, I quote several paragraphs. " The trees on Rutgers 

 College Campus were efiectually protected by spraying with a 

 mixture of one pound of London purple in a hundred gallons of 

 water. In this proportion the larvae are destroyed and the foliage 

 not injured." Six pounds of common wheat flour was added to 

 the above mixture, and in order that it might adhere better to the 

 downy underside of the leaves, one gallon of common kerosene 

 emulsion was added. This mixture proved very satisfactory for all 

 purposes. Concerning methods of applying the above Prof. Smith, 

 says: " The results of an application of this mixture are quickly 

 noticeable. The young lai"V£e succumb almost immediately, and 

 many of the eggs are destroyed where they are fairly hit by the 

 mixture. Another point to be observed is the time of application. 

 This should be just after the eggs are hatched, and before the 

 larvae become half grown. One application will probably be suf- 

 ficient, though the tree may be somewliat eaten by the imago. If 

 the trees to be protected are small and few in number it will pay 

 to spray twice, once when the beetles are beginning to deposit and 

 again when the eggs are hatching. If sprayed too early a tew 

 beetles will be destroyed which will lie replaced by later arrivals 

 and little good is done. If sprayed too late the advanced lai-vae 

 will be ready for pupation and will not be affected. Many a man 

 has tried poisons to destrov insect pests and declared them to be 

 failures; they were not so because of any fault of the poison, hut 

 simply because they were put on at the wrong time and in the 

 wrong way. It is advisable to avoid wetting the trees more than 

 necessary. The finer the spray, and consequent coating of pois- 

 onous mixture, the better the results." The elms referred to by 



