APPENDIX. 309 



Insecticides. 

 Paris Green: 



Dry Paris Green — Flour, 20 pounds. 



Paris Green, 1 pound. 

 Mix tlie two and dust the plants when they are moist from dew 

 or rain. 



Wet Paris Green — Paris Green, 1 pound. 



Bordeaux mixture or water, 50-300 gallons. 

 For apples or pears use 1 pound to 150 gallons of Bordeaux mix- 

 ture or water. If water is used add 2 pounds of fresh slaked lime 

 to prevent injury to the foliage. 



For cherries or plums use 1 pound Paris Green to 300 gallons of 

 Bordeaux mixture or water. 



For potatoes use 1 pound Paris Green to 75 gallons of Bordeaux 

 mixture or water. 



For cabbages and cauliflowers use 1 pound Paris Green to 80 gal- 

 lons resin lime mixture after the plants begin to head. 



Arsenlte of Soda: 



White Arsenic, 1 pound. 



Sal Soda, 4 pounds. 



Water, 1 gallon. 

 Mix and boil about 15 minutes or until the arsenic Is all dissolved. 

 Add just enough water to make up for that lost in boiling, then put 

 In jugs or bottles until needed. Two quarts of this solution may be 

 used in the place of 1 pound of Paris Green by adding about 4 pounds 

 of fresh slaked lime or by combining with Bordeaux mixture in which 

 there is an excess of lime. This spray forms a cheap substitute for 

 Paris Green, but is liable to burn the foliage of tender plants. 



Arsenate of Lead: 



Lead acetate (sugar of lead), 22 ounces. 



Sodium arsenate, 8 ounces. 



Water or Bordeaux mixture, 100 gallons 



Dissolve each separately; then mix the two together and pour 

 this mixture into the required amount of water, or if it is to be used 

 with the Bordeaux mixture, pour it into the lime wash before that is 

 mixed with the copper sulfate solution. 



The sodium arsenate dissolves in water quite readily. Dissolve It 

 In about a gallon of water. Into It pour the dissolved lead acetate to 

 the required amount and let it settle. Then take a small quantity of 

 the liquid in a cup to test it. This Is done by adding to it a little 

 more of the lead acetate solution. If a white substance then forms. 

 It signifies that not enough of the lead has been used to combine 

 with all of the arsenic, and therefore more lead acetate should be 

 added to the mixture. Then pour this mixture into the lime wash if 

 it is to be used with the Bordeaux mixture. 



While arsenate of lead may be made at home by the above form- 

 ula, yet it is commonly purchased in a paste form in sealed packages. 

 The home made article is more finely divided and stays in suspension 

 longer than the commercial form; yet the difficulty of getting re- 

 liable materials with which to make It oft-times prevents its being a 

 success. 



Arsenate of lead has the merit of adhering well to and being 

 harmless to the foliage. As a rule, about three pounds of arsenate 

 of lead are required for fifty gallons of water, while of Paris Green, 

 its most popular competitor, about one-third to one-half pound would 

 be required. This would make the arsenate of lead cost for spraying 

 purposes from two to two and one-half times as much as Paris Green. 

 On the other hand, the arsenate of lead adheres so tenaciously to the 

 foliage that less applications of it are usually necessary. This is es- 

 pecially true in rainy weather. This feature of it, together with Its 



