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CONTROLLING INSECTS AND DISEASES 



giving no chemical reaction. It is used at the rate of 1 to 2 

 pounds to each 100 gallons of spray. Soybean flour and lime 

 (1 pound of each to 100 gallons of the mixture) have given 

 good results. 



c : 4. Lignin pitch is used with lead arsenate and lime- 

 sulfur combinations and as an emulsifier for home-made 

 lubrication oil emulsions. It is applied at the rate of % pound 

 to 100 gallons of the mixture. 



(d) Consider Preparation of Materials at Home or Their 

 Purchase jrom Commercial Concerns, Whether or not mate- 

 rials for the spraying program should be made at home depends 

 on the complexity of the processes of manufacture, the quan- 

 tities of spray materials required, the equipment needed, and 

 the final saving in cost over the prepared product. Some 

 materials deteriorate on standing and should be prepared 

 just prior to their use. Others may be prepared in advance 

 and stored until needed. It is not feasible to attempt to 

 manufacture arsenate of lead at home. The same is true 

 of the tobacco preparations, with the exception of the dusts 

 which are sometimes prepared by growers using them in large 

 quantities. 



d : 1. Consider the preparation of lime-sulfur. Lime- 

 sulfur may be prepared at home. It is made by large growers 

 in some sections, especially where the freight rates on the 

 commercial products are high. The equipment needed is not 

 extensive. 



A common formula is: 



Burned or quicklime 50 pounds 



Sulfur 100 pounds 



Water 50 gallons 



Experiment stations will furnish directions for making. 



Commercial forms of lime-sulfur are now so well standard- 

 ized, however, so uniform in test, and produced in such enor- 

 mous quantities that many growers prefer to use them. 



