EXPERIMENT STATION BULLETINS. 249 



ture there seems to be little difference in the effect, whether one poaud of 

 copper sulphate is used to ten gallons of water or for fifteen gallons, but if 

 much more water is used the efficiency is reduced. For all applications 

 before the leaves appear we prefer to use at the rate of two pounds of 

 copper sulphate to twenty gallons of the mixture, and increase the 

 amount of water by about five gallons for each subsequent application. If 

 the first and second sprayings are made in a thorough manner at the proper 

 times, i. e., before the buds start, and just after the petals have fallen from 

 the blossoms — a third application at from three to four weeks after the sec- 

 ond will suffice unless it is desired to control the curculio by means of 

 Paris green, in which case an intermediate spraying with that material alone, 

 about two weeks after the second application of Bordeaux mixture, will be 

 desirable, although, as the cost of the material is so small, it will be well to 

 add the copper sulphate, the lime being necessary to prevent the burning 

 of the foliage by the Paris green. 



Ammoniacal Carhonaie of Copper. — Dissolve three ounces of copper 

 carbonate in 3 pints of ammonia water ('26°) and dilute before using with 

 32 gallons of water. The original solution if kept in a glass stoppered 

 bottle will retain its strength for a long time. 



This mixture seems rather less effective than the Bordeaux mixture in 

 the destruction of fungi and is more likely to injure the foliage; in fact, it 

 is hardly safe to use it upon the peach, particularly as it is only applied in 

 midsummer, when it is not desirable to use lime upon the ripening fruits. 

 So far as the spotting and poisoning of the fruit with the preparation are 

 concerned, there is but little danger, although it is not advised to spray 

 fruits with it that are to be gathered within three weeks. 



As sold upon the market, copper carbonate costs from 30 to 50 cents per 

 pound, but it can be made for less than half those prices. To make it, 

 dissolve one pound of copper sulphate and one pound of carbonate of soda. 

 Pour together and, in the precipitate that forms, there will be the equiva- 

 lent of eight ounces of copper carbonate. Turn the water off and either 

 allow the precipitate to dry, or use at once as desired. The modified 

 eau celeste is practically the same as the ammoniacal carbonate of copper, 

 made as above, except that it contains more copper carbonate and it is 

 rather more effective. 



INSECTICIDES. 



In order to make an efficient use of insecticides one must not only under- 

 stand the methods in which they act, but he should have at least some 

 general information regarding the habits of the insects to be treated. 

 Many of the failures reported are due to lack of this knowledge, since a 

 remedy may be used that is unsuited to the purpose, as a little knowledge 

 would have shown. Not only are remedies for sucking insects used upon 

 leaf-eating forms and vice versa, but many persons seem to have an idea 

 that spraying will prevent all injuries to their fruit, and, without giving 

 thought to the proper remedy, expect to destroy insects by the use of 

 fungicides, or the reverse. 



Ar seniles. — For all leaf- eating insects some form of poison should be 

 used, when it can be placed so that they will obtain it. The more com- 

 mon remedies are Paris green (arsenite of copper) and London purple 

 (arsenite of lime). White arsenic and corrosive sublimate are used by 

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