4^8 MINNESOTA STATE HORTICULTURAL SOCIETY. 



DUST SPRAYrNG. 



G. C. JOHNSON, KANSAS CITY, MO. 



I am invited to lay before you a comparative statement of the 

 value of both systems of spraying trees, plants, vines and vegetables, 

 based upon our own experience in the orchard and supplemented by 

 the experience of the commercial orchardists who have used the dry 

 process since we brought it into public notice in the season of 1900. 

 While we have kept in very close touch with those who have used 

 the dry process of spraying and are familiar with the results ob- 

 tained better than any other person, yet the opportunity of meeting 

 many of our patrons personally at the late universal exposition in 

 St. Louis broadened the scope of our own experience and verified 

 many points on which we had been experimenting. We will, there- 

 fore* endeavor to lay before you the results obtained so far in the 

 use of the dry conveyor and its value to the fruit grower, as com- 

 pared with what has been accomplished by the use of water for the 

 same purpose, under the following title, the simple change from 

 water to lime dust as a conveyor of the standard formulse for 

 spraying, and what the change means to the fruit grower. 



The conditions you have to meet, climatic and otherwise, in the 

 growing of fruit in Minnesota are different from what we have to 

 contend against in Missouri, and these varying conditions and differ- 

 ent insect pests peculiar to our varied climate in the fruit-growing 

 sections of the United States must be intelligently studied. In the 

 citrus orchards of Florida and southern California, for instance, the 

 rust mite and the red spider are of very grave concern to the fruit 

 grower. The dry conveyor is the only one that can be successfully 

 used in combating these pests. In Colorado and the higher altitudes, 

 they are not bothered with fungous disease as we are in the middle 

 west, but the codling moth is very much in evidence. The natural 

 conditions that must be observed to successfully control this pest re- 

 quire perfect distribution of arsenic and in unlimited quantity. Both 

 of these conditions are obtained by the simple change of conveyor 

 from the wet to the dry form. The superabundance of lime, the 

 neutralizer, preventing the burning of the foliage, the amalgamation 

 of the arsenic with the lime dust is perfect, and by using nature's 

 distributors, the air and the wind, the distribution is perfect and 

 cannot even be approached by the artificial distribution of the force 

 pump. 



In the treatment of fungus we have a far more difficult proposi- 

 tion. We know the remedy, blue stone, or sulphate of copper, but 

 how to apply it so as to get the direct, positive action of the rem- 



