FISHERIES, GAME AND FORESTS. 



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Formulas for arsenical preparations. Arsenate of lead may be prepared as fol- 

 lows : Dissolve II ounces of acetate of lead (sugar of lead) in four quarts of water 

 and four ounces of arsenate of soda ($0% purity) in two quarts of water, each lot in 

 a wooden pail, and then add the solutions to the required amount of water, which 

 for most leaf-eating insects will be about 100 gallons. This substance can be used 

 in much greater strength without danger of injuring the plants, provided it is prop- 

 erly prepared. It is of special value against the elm leaf beetle because of the adhe- 

 siveness of the poison, and for this insect it is better to use the amounts given above 

 in but 50 or 80 gallons of water. This poison has also been placed on the market in 

 a paste form ready for dilution with water. Thus prepared it has all the good 

 properties of the freshly made material and may be used with confidence. The 

 crystalline arsenate of lead can not be recommended as it is heavier and does not 

 adhere to the foliage as well as the other form. 



Paris green or london purple, and also certain other arsenical preparations, are 

 used with great success in combating leaf feeders. One pound of either of these 

 poisons to 100 to 150 gallons of water is the proportion usually employed. It is 

 well to add also a pound of recently slacked lime (mix with considerable water and 

 strain before adding) in order to lessen the danger of burning the foliage. It is 

 essential that either of the above mixtures be kept well stirred in order to secure 

 uniform results, as the latter named poisons, in particular, sink rapidly to the bottom 

 of the tank. 



Formulas for contact insecticides. Kerosene emulsion is one of the most import- 

 ant of the contact insecticides, that is, those which must be actually thrown onto 

 the insect in order to secure results. It may be prepared as follows : Dissolve one- 

 half pound of hard soap in a gallon of boiling water and while it is still hot add two 

 gallons of kerosene, and emulsify either by stirring rapidly or by repeatedly forcing 

 it through a pump and fine nozzle. A white, uniform creamy mass which does 

 not break up into oil and water should be obtained and this can then readily be 

 diluted with water, the usual amount being nine parts water to one of the emul- 

 sion. A sour milk emulsion should be used in limestone regions, two gallons of 

 kerosene to one gallon of sour milk, emulsify as described above and dilute. The 

 IO per cent mechanical kerosene emulsion can be used in a similar manner, pro- 

 vided the pump can be depended upon to give reliable proportions. One pound 

 of whale oil soap to four gallons of water can be used si fely on foliage and is as 

 effectual as the kerosene emulsion for similar purposes. 

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