PEACH YELLOWS. 289 



fact, three hundred and fourteen trees became diseased, by yellows in 1887, 

 and an additional three hundred in 1888. 



4. In 1887, in orchard No. 7 of this report, I very carefully examined the 

 collar and trunk roots of seventeen trees which were suffering from yellows. 

 Six had been severely injured, by borers or bruises; nine had been slightly 

 injured ; and two bad never received bark injuries of any sort. Healthy 

 trees in the same orchard were also found to be injured by borers and bruises; 

 while those diseased by yellows did not seem to be affected proportionately to 

 the extent of the injury. 



5. According to Mr. William HuvJson, orchard No. 8 of this report was 

 never much injured by borers. 



6. In 1887, in orchard No. 12 of this report, I found seven trees unmis- 

 takably diseased by yellows which had no borers and never had any, and had 

 never received injuries of any sort oti the trunk, collar, or trunk roots. 



?. In 1887, in the southwest corner of orchard No. 14 of this report, six 

 healthy and six diseased trees were very carefully examined for borers and 

 bruises. Four of the diseased trees were entirely free ; two were slightly in- 

 jured. Four of the healthy trees were entirely free ; two were slightly injured. 

 In 1888, three of the six healthy trees became diseased. These were three of 

 the four trees which had never been injured. The entire orchard appeared 

 to be very free from injury by borers. The trees were "wormed"' in August, 

 1884, 1885, and 1886, but not many borers were found. None have been 

 allowed to remain in the trees. 



8. The two old orchards of Charles Wright, Seaford, Del., have suffered 

 severely from borers for years, but yellows has never appeared. He now 

 examines his trees twice a year, and says he would lose them if he did not. 

 This year out of some trees he took as many as twenty borers. 



At E. B. Emory's, in Spaniards' Neck, Queen Anne county, Md., a region 

 yet almost entirely free from yellows, I saw a few trees which might throw 

 doubt on the relation of borers to yellows were it not for the facts already 

 cited. 



In a block of five hundred trees, first examined in 1887, I found two or 

 three hundred which were more or h ss dwarfed and sickly looking. Several 

 of these trees were suspicious, but I saw no premature peaches, and could not 

 say positively that any were suffering from yellows. The remainder of the 

 block looked healthy, as did all the rest of the orchard, and all the other or- 

 chards on that farm and on all the farms in the Neck. Some of the trees 

 had suffered from borers, but after examining sixty I came to the conclusion 

 that only a very small percentage had been seriously injured. In forty-two 

 I found no indications of borers ; but in this case my examination was not 

 exhaustive, and I may have ovei looked some. These trees may also have 

 suffered from root aphides, as they came from a region where the nurseries 

 were badly injured by this insect some years ago. Anyway this block, in the 

 middle of an otherwise healthy orchard, presented a very striking contrast. 

 The trees on each side were of the same age, but procured from other 

 localities. 



In the fall of 1887 or spring of 1888, thirty or more of the worst of these 

 trees were cut back so that nothing remained save the trunk and the stubs of 

 the main limbs. When examined in the summer of 1888, 1 found some healthy; 

 some dead ; and some diseased in the following way: The stubs of the limbs 

 of twelve trees were covered with a pale, yellowish green much branched 



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