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We had previously had infestation at College Park on plum trees. 

 It was not until 1908 that it was found to be indigenous to Pennsyl- 

 vania, New York, and some of the Western States, and most of the 

 States east of the Mississippi. It seems to have a general range of 

 distribution, and has not been of any marked importance except 

 during the last year. It was found to affect the plum and peach 

 tree primarily, but will also be found in others, as, for instance, the 

 sycamore and oak. In the plum orchard at the college, it was found 

 that there was a fungus there that cleaned it out; and that started 

 our work in the orchard at Smithsburg. I will cite briefly the man- 

 ner of injury by this pest. It does not do its injury as does the San 

 Jose Scale. The San Jose Scale does its injury by devitalizing the 

 tree, sucking the juices of the tree, and killing it. This insect, 

 though sucking the juices of the tree and leaves, does not seem to 

 kill the trees outright to the extent that the San Jose Scale does. It 

 seems to attack only the outer twigs, leaving the larger limbs free, 

 and therefore, does not kill the tree; but the injury is due to the 

 fact that the scale insect secretes a honey dew, which gives rise to a 

 dark fungus that lives on the honey dew, and affects the fruit. 

 This fungus spreads all over the fruit on the tree, making it dark^ 

 unpresentable; and unsalable, and the loss has been due to the fact 

 that the fungus scarred the fruit, so as to make it unsalable at the 

 proper prices. So, it is a question of considerable importance, and 

 the spread of it this y^ar leads us to believe that we have certainly 

 got to get after it; and the question is, how should we get after it. 

 In our tests with the Lime Sulphur and the miscible oils in 1907, 

 we secured fairly good results. Thinking that the Lime Sulphur 

 would be sufficient, and that the orchards that had been sprayed with 

 Lime Sulphur for the San Jose would be protected, we felt secure. 

 We found, however, that the Lime Sulphur made no difference. It 

 spread through the whole orchard; We are up against it as to what 

 to do at the present time. There are several other parties around 

 Smithsburg that have it more or less, but not to the extent of the 

 orchards referred to. 



This insect winters as an immature female. Early in the spring 

 it begins to grow, and reaches maturity about the first of May. 

 Later it begins laying eggs, and itself dries up, like the oyster shell 

 scale. The eggs hatch out about the first of June. The young ones 

 crawl out. Instead of inserting their beaks on the limbs, as does the 

 San Jose, these insects go out on the leaves, up and down the ribs 

 on the under side of the leaves. If you examine the peach trees the 

 first of June, you will find a soft, flat little scale out on the under 

 side of the leaves, up and down the mid rib. They stay there six 

 weeks, secreting their honey dew, and the fungus drops down and 

 gets all over the peaches. In about six weeks they return from the 

 leaves to the twigs, and remain- there, developing over winter as an 

 immature female. This scale is unique in its habits, in that it infests 

 both the twigs and the foliage. We had thought that spraying the. 

 trees just as the eggs are hatched, or when they are going out on 

 the leaves, with kerosene emulsion, would kill them ; but this did not 

 prove to be the case. The emulsion should be applied just as the 

 eggs are hatched. I cannot at this moment give you any advice as 

 to the controlling of this pest; but experiments are under way, and 



