24 THE APPLE LEAF HOPPER 



killed. The sides and top of the Wallace sprayer were covered with 

 dead hoppers, the greater proportion of which were adults, and but 

 few nymphs. The soap solution gave, as near as could be determined, 

 practically the same benefit as the 10% kerosene emulsion solution. 



Tobacco-soap Solution: Twelve pounds of tobacco stems were 

 steeped in 12 gals, of water for an hour and a half, and five bars 

 (60 oz.) of Lenox soap were added. The soap was allowed to dis- 

 solve, and enough water added to make fifty gals, of the solution. 

 This was applied to the apple stock with the Wallace Power sprayer. 

 The same difficulty was experienced in this case as in the case of the 

 fish oil soap, namely that of hitting the hoppers in the curled leaves. 

 Where hit young hoppers were killed, but the spray had little or no 

 effect upon the adults. Compared with fish oil soap, and the kerosene 

 emulsion spray, the tobacco soap solution was considerably less 

 effective than either of the other two. 



Resin Wash: This wash was made as follows: Eight lbs. of 

 resin and 6 lbs. of common washing soap were boiled in two gals, of 

 water for nearly two hours. After boiling, the mixture was diluted 

 to about 10 gals. It was then poured into the sprayer tank, and 70 

 gals, more water were added, thus making the proportion of 1 gal. of 

 the stock solution to 7 gals, of water. 



An attempt was made to spray this solution upon apple stock 

 with the Wallace Power sprayer. The resin, however, adhered to the 

 sides of the pump cylinder, forcing the plunger to work with great 

 difficulty, and giving insufficient pressure with which to spray. Finally 

 the attempt to spray W'ith this mixture had to be abandoned. On 

 those trees where it was applied the resin wash covered the leaves 

 thoroughly, with the exception of the curled leaves in the tops of the 

 trees. The wash was effective when touching nymphs on uncurled 

 leaves. As far as could be determined, there was no efifect upon adult 

 hoppers. 



STICKY SHIELDS. 



These have been used in New York and elsewhere against the 

 Grape Leaf Hopper, and a trial was made with them at Owatonna 

 in 1907. 



A light frame was made 3 by 4 feet with a handle, and covered 

 with heavy cloth; the cloth was then covered with O. & W. Thum's 

 Tree Tanglefoot, a one-pound jar making a heavy coating to within 

 two inches of the edges of the frame. This grade of tanglefoot is 



