134 TRANSACTIONS OF THE ILLINOIS - 



tion of our apples — especially late varieties — were small, scabby 

 and cracked, but as this was so universal, spraying, probably, 

 did not affect it one way or the other. In one orchard a number 

 of Duchess and Fourth of July trees bore a full crop of fair,, 

 sound apples, with scarcely a wormy one in the lot. The few 

 Transcendant Crabs and Maiden's Blush were comparatively 

 free, while of later kinds in the same orchard, quite a propor- 

 tion were wormy. One orchard, mainly of winter apples, which 

 is entirely isolated from other bearing trees, seemed to be very 

 free from wormy apples. This was sprinkled twice, and at the 

 same time as the other orchards. 



These are the facts as I observed them ; now what caused the 

 difference in results? Did it "just happen so," or can we find a 

 cause for it? Perhaps you will be interested in the deductions 

 which I made. 



The isolated orchard was free from worms last year, (1888) 

 which we can credit to the spraying that season, or the light crop 

 of '87, or both, and consequently there was little to breed a crop 

 this season, and what few eggs were deposited were kept in sub- 

 jection by the spraying. 



The early apples in the other orchard were near trees which 

 were not sprayed either season, but the fruit was matured before 

 the second crop, which entomologists tell us is the most numerous 

 and destructive, had got in their work, but the later kinds in the 

 same orchard did afford the moths the opportunity to deposit 

 their eggs, and consequently the wormy apples. 



My conclusions, therefore, are that spraying apple trees with 

 arsenical poisons is beneficial, and not at all injurious, if properly 

 and intelligently done. I would spray two or thiee times in the 

 course of the season, at intervals of about a week, commencing 

 just about the time the blossoms fall, and ending before the apple 

 gets heavy enough to hang downward. This I am convinced will 

 keep the canker-worm in subjection, and materially lessen the 

 ravages of the codling-moth, and I believe if it could be univer- 

 sally done, would well nigh exterminate it. 



A word of caution here. Do not go on the principle that the 

 more of a good thing the better, or you may burn the foliage of 

 your trees severely. One pound of London Purple to 160 gallons 

 of water is strong enough for the first application, and unless tbe 

 weather is damp or rainy, I would advise weakening succeeding 

 applications to one pound to 180 or 200 gallons of water. 



At some future time I intend to try the experiment of.a mixture 

 of a solution of London Purple with an emulsion of kerosene. 



My apparatus for spraying is simple. Two wagons are fitted^ 

 each with a 160 gallon cask mounted on its side, and a Field's 

 Force Pump, which can be changed from one cask to the other. 

 In operation, the poi«on is put in the casks before filling with 

 water, and by the time the wagon gets to the orchard, the con- 



