244 The Commercial Apple Industry 



taken to use enough water to prevent too violent slaking 

 or burning, although too much water is objectionable, 

 since this will drown the lime. Mix the sulfur to a thin 

 paste and add the lime, then the desired quantity of water. 

 After the full amount of water has been added, the cook- 

 ing-vat should be marked or a notched stick used to show 

 the original amount of water. Keep adding hot water 

 from time to time to replace that which has evaporated. 

 The solution should not be allowed to boil down stronger 

 than one-half gallon to each pound of sulfur, nor should 

 there ever be much of an excess of water. The solution 

 should be boiled for at least forty-five minutes but not 

 longer than one hour. It is important that boiling should 

 proceed vigorously and that the mixture should be stirred 

 constantly. After the lime-sulfur solution has been made, 

 it should be strained in order that the undissolved particles 

 may be removed. Straining should be through an iron 

 wire (never copper) 30 to 50 mesh to the inch. The solu- 

 tion should be allowed to cool before being tested with a 

 hydrometer. If the solution is left exposed, a film of 

 oil should be poured over the surface to exclude the air. 

 It is highly important that all home-made lime-sulfur be 

 tested with the hydrometer, otherwise the grower is merely 

 guessing as to the strength of the spray. The sediment 

 obtained in the manufacture of home-made lime-sulfur will 

 be useful in painting the trunks of the trees. 



Nicotine solution is recognized as a standard contact 

 insecticide for summer spraying. It is particularly effect- 

 ive against aphids and may be used without injury to the 

 foliage. A solution of nicotine sulfate containing 40 per 

 cent nicotine such as Black Leaf 40 is the common com- 

 mercial form. Proper dilution is given at 1 to 800 and 



