538 STATE BOARD OF AGRICULTURE. 



some other dusts. Some little time will be required to establish it as 

 beyond doubt the equivalent of arsenate of lead for use in watery mix- 

 tures. At present we are not recommending its use on stone fruits. It 

 is hoped that eventually arsenate of calcium will take a place of equal 

 importance with arsenate of lead in many sorts of spruviiis operations, 

 and' tliat it will prove as reliable when mixed with fnn<;ieides and con- 

 tact sprays as the better known poison. The strength ordinarily recom- 

 mended is % pound of the powder to 50 gallons of water, lime-sulphur 

 or Bordeaux. When used alone in water, it is advisable to add two or 

 three pounds of freshly slaked lime to each barrel of the.spray. 



PAKIS-GREBN ANn LIME. 



Never mix Paris-green with lime-sulphur in any form. Paris-green can, 

 however, be used with Bordeaux-mixture with safety. 



For spraying from a barrel, the writer has found the following method 

 very useful: Place from ^4 to 14 pound of good lump lime, or uiislake<l 

 lime, in each of 3 or 4 tin pails which will hold about ?> quarts or less. 

 Old cans or crocks will answer just as well. Add enough hot water to 

 slake it into a thin cream or paste. Now add to each lot 14 pound of 

 Paris-green, previously weighed out, and placed in paper bags; stir while 

 the lime is hot and allow to stand for some time. Now measure out about 

 44 gallons of water in your spraying barrel, and make a mark that will 

 show how high it comes in the barrel; add the contents of one tin pail 

 (viz., 1/4 pound of Paris-green and i^ pound of quick-lime slaked) into 

 the 44 gallons of water in the barrel. Stir well and spray. The pails 

 or crocks can be used one at a time and re-filled occasionally so that 

 the stock is always on hand ready for use. 



ARSENATE OP CALCIUM KEDZIE-MIXTURE. 



This mixture, originated by the late Dr. R. C. Kedzie, of this station, 

 is cheap, but it has the disadvantage of lacking a warming color. It is 

 a good substitute for Paris-green, but must be made with care, and stored 

 in well-labeled jugs. It is made of white arsenic (not arsenate of lead) 

 and carbonate of soda. 



Dr. Kedzie in giving directions for its preparation says : "Dissolve 

 the arsenic by boiling with carbonate of soda, and thus insure complete 

 solution; which solution can be kept ready to make a spraying solution 

 whenever needed. To make the material for eight hundred (800) gal- 

 lons, of spraying mixture, boil two pounds of white arsenic with eight 

 (8) pounds of sal-soda (crystals of carbonate of soda — 'washing soda' — 

 found in eveiy grocery and drug shop) in two gallons of water. Boil 

 these materials in any iron pot not used for other purposes. Boil for 

 fifteen minutes or until the arsenic dissolves, leaving only a small muddy, 

 sediment. Put this solution into a two-gallon jug and label, 'Poison,' 

 stock material for spraying mixture." 



"The spraying mixture can be prepared whenever required,, and in the 

 quantity needed at the time by slaking two pounds of (stone or lum])) 

 lime,* adding this to forty gallons of water; pour into this a pint of the 



*Three pounds of fresh hydrated lime may be made to take the place of the two pounds of 

 stone or lump lime. 



