174 STATE HORTICULTURAL SOCIETY. 



able growth and appeared to be free from disease. These trees were budded 

 in a locality where yellows is very prevalent and have remained there ever 

 since, i. e., over three and a half years. Therefore, it can not be assented 

 unqualifiedly that the diseased trees resulted from the insertion of diseased 

 buds, since the possibility of subsequent infection is not excluded. 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 interesting 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 terminal 

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

 was about four 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 Washington, was 

 inoculated in a dozen terminal branches with buds taken from one of the 

 ten 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 indisputable evidence that the 

 disease can be spread in this way, although it seems very probable. Several 

 extensive experiments of this kind are now in progress. In Experiments 1 

 and 2, in all or almost all of the inoculations, there was a distinct union 

 between the bud and the stock, i. e., between the diseased and healthy 

 tissues, some months prior to the first appearance of symptoms in the 

 stocks. 



Experiment 5. — In order to be absolutely certain as to the healthy 

 character and sound constitution of the seedlings, stones were procured in 

 quantity from three localities free from yellows. These were planted 

 November 8, 1889, upon well drained and fertile soil in the grounds at 

 the Department of Agriculture. Row No. 1 were Tennessee pits. "These 

 pits were bought of Johnson & Stokes, Philadelphia, and came from 

 London, Tennessee." I procured them from Charles Wright, Seaford, 

 Delaware. Row No. 2 came from Sussex county, Delaware, and were also 

 procured from Mr. Wright, who had purchased them for his own use. 

 Concerning them he wrote: "The Delaware pits were collected by myself 

 of William P. Brown of Seaford and were saved from old seedling trees 

 in his orchard near town." Plow No. 3 came from Caroline county, Mary- 

 land. They were collected by J. W. Kerr of Denton for his own use. 



The seedlings came up satisfactorily and made a good growth in the 

 season of 1890. About 100 of each row were inoculated and the rest were 

 reserved for fixture experiments." 



