22 PEACH YELLOWS. 



At the time of removal Mr. Barnard reserved ten trees from experiment 

 4, and set them with others of the same age in an orchard on his farm. 

 According to his statement, January 10, 1889, they made a good 

 growth in 1888 and were as healthy as any trees. September 20, 1890, 

 Mr. Barnard reported that the trees were still healthy, but they were 

 not personally inspected until January 26, 1891. 



At that date the following conditions prevailed : One tree was gone ; 

 one tree had made no growth worth mentioning and was dead with 

 symptoms of yellows ; three were much smaller than should be and 

 were suffering from yellows or at least presented what seemed to me 

 satisfactory symptoms ; one was doubtful ; and four were nice trees. 

 The latter had made a reasonable growth and appeared to be free from 

 disease. Plate xxv shows the best one of the healthy trees. These 

 trees were budded in a locality where yellows is very prevalent and have 

 remained there ever since, i. <?., over 3J years. Therefore, it can not be 

 asserted unqualifiedly that the diseased trees resulted from the insertion 

 of diseased buds, since the possibility of subsequent infection is not ex- 

 cluded. The possibility, however, is not great, because the trees were 

 badly dwarfed, as if they had been diseased from the start, The trees 

 which still appear to be healthy are, therefore, the only really interest- 

 ing ones. Their behavior during the next year or two will be a matter 

 of considerable interest, as throwing additional light on the question 

 whether the whole tree is diseased when symptoms appear in any part 

 of it. 



For this experiment the buds were selected with great care from ter- 

 minal branches upon the healthy-looking side of a diseased seedling tree 

 which was about 4 years old. If any portion of the tree was free from 

 the disease these branches should have been. The buds were cut and 

 inserted September 7, 1887. The tree from which they were taken 

 manifested symptoms of yellows in all parts in the spring of 1888, and 

 died that summer. 



One failure of another kind remains to be recorded. A large and 

 vigorous seedling tree in the yard of Prof. Cleveland Abbe, in Wash- 

 ington, was inoculated in a dozen terminal branches with buds taken 

 from one of the 10 trees set on the Department grounds and described 

 under Experiment 1. The buds were cut August 15, 1889, and inserted 

 the same day. The growth of the tree from which the buds came had 

 been stronger and healthier looking than that of the others, but fully 

 one-half of the winter buds were then germinating and the inserted 

 buds were of this character. 



This tree has remained healthy, but no stress should be laid upon the 

 fact because owing to the use of a dull knife or to the fact that the 

 shoot-axes had already pushed, all of the buds dried up in a few days 

 and entirely failed to unite with the branches. So far as relates to the 

 propagation of yellows it must be classed with pruning and other 

 experiments of simple contact and I have not yet obtained any indis- 



