30 N. H. AGR. EXPERIMENT STATION. [Bulletin 157 



copper by the addition of a few drops of potassium ferrocy- 

 anide solution. If there is an excess of copper sulfate present 

 a conspicuous brown precipitate will be formed. In such a case 

 more of the lime solution should be added. The absence of this 

 precipitate indicates that the amount of lime already added has 

 been sufficient to combine with all of the copper sulfate. 



It has frequently been advised that Bordeaux should not be 

 used after standing overnight, since when the precipitate has 

 once thoroly settled it can never be got into as fine a state of 

 division again. While the physical condition of old Bordeaux 

 is not all that could be desired, it is far better than that of the 

 average patent mixture, and if the difficulty of frequent prep- 

 aration prevents the use of home-made Bordeaux the depreciation 

 with age should not be too greatly emphasized. 



Lime-Sulfur. The importance of lime-sulfur as an insecticide 

 and its growing favor as a fungicide have caused considerable 

 attention to be given to its preparation in recent years. The 

 folio wdng is a very satisfactory formula: 50 pounds best stone 

 lime, 100 pounds sulfur, water enough to make 50 gallons of 

 solution at finish. The quantities may be proportionately 

 reduced as desired. 



Place the fresh stone lime in a kettle or other vessel to be used 

 and slake slowly. Put in the sulfur, mixing it thoroly with the 

 slaked or slaking lime, adding enough water to maintain a thin 

 paste. Any lumps of sulfur or lime should be thoroly broken up. 

 When slaking and mixing are completed the solution may be 

 diluted to 50 gallons. Boil for about one hour, with occasional 

 stirring. If the boiling has been sufficient, the sulfur will have 

 entirely gone into solution, having combined with the lime 

 to form a clear reddish-yellow compound. Enough water should 

 be added to replace that lost in boiling, bringing the quantity of 

 the solution to 50 gallons again. The solution is now ready to 

 be diluted for use. For summer application on the apple orchard 

 each gallon of this lime-sulfur should be diluted to 25 or 30 gallons. 



Prepared lime-sulfur mixtures can be obtained on the market. 

 A number of companies are selling a good product, and the com- 

 mercial lime-sulfur has much more in its favor both as to 

 quality and price than the patent Bordeaux. It is usually 

 stronger than that obtained by the above method of preparation 



