FORMULAS FOR SPRAYING MIXTURES 



fifteen gallons of water and boil this mixture for about an hour, 

 or until the mixture becomes a deep orange-red or a deep green. 

 It may take on either of these colors; lime never seems to act 

 twice alike in this respect. Add enough water to bring the 

 volume of the mixture up to fifty gallons and it is ready to use. 

 This solution should test about 1.04 specific gravity. 



Both the commercial and the home-made mixture, at the 

 strength directed here, are to be used only on dormant trees, 

 and must not be used on foliage. At this strength it will burn 

 nearly all the leaves off if it is applied after the buds open, but 

 it is no stronger than needed for winter work. Properly diluted 

 and with arsenate of lead added, lime-sulphur is a most valuable 

 summer spray. See formulas. Numbers i, 2 and 3 (self-boiled 

 lime-sulphur and diluted lime-sulphur solutions must be added 

 to prevent burning foliage). 



8. Kerosene Emulsion. Make a stock solution with one-half 

 pound of hard soap, one gallon of hot water (soft) and two 

 gallons of kerosene. Chip the soap fine and dissolve it in hot 

 water. Take the vessel away from the stove and from any fire 

 and add the kerosene while the water is still boiling hot. Im- 

 mediately churn this thoroughly, or better, pump it violently 

 back into the vessel until it forms a creamy emulsion. When 

 only a small quantity of the spray is wanted, sour milk can be 

 substituted for soap and water. 



For various purposes you must have various strengths of 

 kerosene emulsion. To dilute for an eight per cent solution, use 

 one gallon of this concentrated mixture in seven gallons of water; 

 to make a ten per cent emulsion, use one gallon with five gallons 

 of water; to make a four per cent emulsion, use one gallon with 

 fifteen gallons of water. The four per cent emulsion can be 

 used without damage on the tenderest foliage, while the ten 

 per cent emulsion will do good work when trees are dormant. 



9. Soluble or Miscible Oils. Chemical manufacturers 

 prepare brands of oil so treated that they fuse readily with 

 cold water. They make efficient and useful sprays, but must 

 be used with caution. When they are too strong, they cause 

 serious injury to plants or trees. In winter, for San Jose Scale, 

 they do excellent work; and in summer, for various enemies 

 requiring a spray of this character, they are many times ad- 

 visable. It is best to get information about the strength at 

 which to spray from the maker of the oil you use, but for the 

 winter spray a strength of one part oil in fifteen parts water 

 almost always will be right. 



10. Soap Solutions. These make a valuable spray for hold- 

 ing in check San Jose and other scales during the summer, and 

 for various other sucking insects. One pound of hard soap in 

 four gallons of water, or one pound of whale oil soap in five gal- 

 lons of water, is the right strength for dormant trees. In any 

 case, dissolve the soap in about one gallon of hot, soft water, then 

 add the remainder of water cold, stirring hard. 



11. Tobacco. Can be obtained in several forms as a 

 liquid, a powder, or in stems, to be used according to conditons. 

 The essential poison of tobacco (sulphate of nicotine) is ex- 



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