462 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



In the check, 4 per cent only failed to produce worms. In the counts 

 that were made of fruit injury, this 43 per cent killing of unhatched 

 worms made a reduction of only 6 per cent in total fruit losses. On 

 the sprayed plat, 24 per cent of the fruit were damaged while 30 per 

 cent were injured on the control rows. 



Nineteen per cent, only, were killed in experiment 10 where the 

 crude oil was used in a dilution of 1 to 15. Here, 26 per cent of the fruit 

 were found to have been injured by the worms as compared with 30 

 per cent in the check. To have obtained good results, a strength of 

 at least 1 to 8 should have been applied. It is clear that an apphcation 

 in this strength should be made only when the trees are entirely dor- 

 mant. 



The results that were obtained from the miscible oil experiments 

 were highly satisfactory in every way. In fact, the figures show such 

 complete efficiency that those skeptically inclined might look upon 

 them with suspicion.' As has been stated before, the miscible oil 

 was applied in four strengths, 5,6,7, and 8 gallons to the 100 gallons 

 of water. Owing to the fact that a delay occurred in the receipt of the 

 material, followed by rainy weather, the emulsions were not applied 

 until April 3, at which time the trees — of the Newtown variety — 

 were beginning to send out foliage. This foliage development was 

 sufficient to give the orchard a faint green coloration. In a few cases 

 the leaves about the fruit spurs had unfolded to such an extent as to 

 expose the tips of the fruit buds. The trees were thoroughly sprayed, 

 in fact drenched, five to six gallons being applied to each. 



On the day following the spraying, the experiments were carefully 

 gone over; little or no foliage injury was observed. Two days later, 

 however, a large amount of foilage burn was found to have resulted. 

 In experiment 11, where 5 to 100 was used, the injury was of little 

 consequence. In the other experiments, the foliage burn was found 

 to increase in direct proportion with the greater strengths of oil used, 

 reaching a rather alarming condition in experiment 14 where 8 to 100 

 had been applied. In this plat practically all of the foliage that was 

 exposed dried up and dropped off within a week or two. At first it 

 was thought that many of the fruit spurs were killed; the leaves all 

 dropped away but most of the buds continued to grow and the result- 

 ing bloom was almost normal though many of the flowers seemed a 

 little smaller than those on the control trees. These were closely 

 watched and soon after the petals fell many of these smaller ones 

 dropped. Upon examining these weaker flowers, the bases of the 

 stems were found to invariably possess a brown discoloration — in 

 some cases they even seemed burned in much the same manner as 

 that found on the leaves. No other injury to the flower buds was 



