New York Agricultural Experiment Station. ' GOT 



During the spring shipping season all the infested stock in Keene 

 & Foulk's nursery was destroyed, and all suspected stock sold, 

 whether washed during the winter or not, was put through the 

 " gas box" (See Gas Treatment.) A good share of the pear trees 

 washed during December was destroyed. On all the latter that 

 were saved, as well as on other stock treated twice with kerosene 

 emulsion, a good many live specimens were found in July. In 

 most cases they appeared to have issued from adults which were 

 fairly well protected around the union of the branches with the 

 trunk of the tree. In other cases the adults were protected by 

 dirt at the base of the tree ; this was especially the case with the 

 one year old stock. Undoubtedly some of the scale insects would 

 have escaped the action of the washes as well as the climatic effects 

 at these points. 



All the one year old stock was injured to such an extent by the 

 kerosene emulsion that it had to be cut back. In some cases the 

 Ijranches of older stock were injured. 



Summer Washes. — Of summer washes only kerosene and crude 

 petroleum emulsions were tested. For the " Pernicious Scale " 

 these washes were tested on one of the most difficult plants to treat 

 that could be found in a nursery, viz., Pyrus japonica. Two rows, 

 each about ten rods long, of one year old plants, were treated. 

 Many of the branches were prostrate on the ground and partially 

 covered by dirt in cultivation. This stock was in Parsons & Sons' 

 nursery of Flushing, N. T., and had received no previous treat- 

 ment. The washes were applied during the time that the first 

 brood of females was migrating from beneath the mother scale, viz., 

 from June 21st to July 22d. The dates of application of crude 

 petroleum emulsion and the strengths used at each application were 

 as follows : June 21st, 1 to 12; July 1st, 1 to lU; July 15th, 

 1 to 11. Kerosene emulsion was applied on the following dates: 

 July 2d, 12th and 22d. Only one strength was used — 1 part 

 emulsion to 10 parts water. 



As the principal object in using these washes was to determine 

 which would destroy the largest number of the young during the 

 period that they were migrating, the date of application was varied. 

 A secondary object was to test the crude petroleum emulsion on the 

 •parent scales. There was a chance that the heavy oils of crude 

 petroleum, which form a gummy emulsion, would either smother 

 the parent scale or prevent the escape of the young from them. 



