HATCH EXPERIMENT STATION, 



HORTICULTURAL DIVISION. 



Correction f^or Bulletin No. 60. 



The formula and direction for the use of the Arsenate of Lead should 

 be changed as follows : 



Formula. 



11 oz. Acetate of Lead. 

 4 oz. Arsenate of SODA. 

 150 gallons of Water. 



This insecticide has the advantage over Paris green that when 

 used in large quantities it will not injure the foliage of the peach, 

 cherry, Japanese plum or other trees of delicate nature. It is how- 

 ever more expensive and its effectiveness in destroying the common 

 insects attacking our fruit and garden crops is not so well proven as 

 that of Paris Green. It should be given a thorough trial especially 

 on those crops where Paris green is known to be injurious. 



'''*This insecticide is easily prepared by putting 11 oz. acetate of 

 lead in 4 qts. of water in a wooden pail and 4 oz. arsenate of soda 

 (50 per cent strength) in 2 qts. of water in another wooden pail 

 and when entirely dissolved mixing in a hogshead or tank containing 

 150 gallons of water, when a chemical reaction will take place 

 forming arsenate of lead as a pure white powder in suspension in 

 the water." If the common 50 gallon barrel or cask is used the 

 formula would be 3f oz. acetate of lead and 1-| oz. arsenate of soda.) 

 " If cold water be used the solution of acetate of lead will require 

 a little time, but however, if the water be hot it will dissolve quickly. 

 It is customary to add from 1 to 4 qts. of glucose to the above 

 amount of water to make the poison adhere more firmly, but this 

 may not be necessary. If it is desired to use larger proportions of 

 the arsenate of lead it is only necessary to use more acetate of lead 

 and arsenate of soda, but always in the proportion given above." 



*Prof. C. H. Fernald in 45th Annual Report of Mass. State Board of Agriculture, 

 1897. 



