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MISCELLANEOUS PAPERS. 



the resulting trees when dug in the autumn showed fairly good unions. 

 The grafts as a whole fell below the wrapped ones in the number of 

 smooth trees. There were more deficient trees in this lot, with the 

 possible exception of those waxed over, owing to defective unions and 

 failures to form a union. 



EFFECT ON CROWN-GALL FORMATION. 



As indicated in the introduction, one of the objects of the experiment ^ 

 was to determine whether by wrapping grafts it would be possible to 

 reduce the number of trees affected with crown-gall. In the following 

 table the total number of trees dug is given; also the kind of wrapping, 

 and the number and percentage of smooth trees, crown-gall trees, and 

 hairy-root trees : 



Table 11.— Comparison of smooth trees and trees affected with crmvn-gall and hairy-root, 

 resulting when different methods of grafting were used. 



A study of this table will show that the wrapping reduced the number 

 of crown-gall trees very materially, but the results given should be 

 considered as preliminary and the figures as relative rather than abso- 

 lute. Only a small number of the trees under test have so far been 

 dug. The remainder will be dug after one or two years' growth. 



The most effective wrappings so far as the true crown-gall is con- 

 cerned, was that made of rubber (86.5 per cent of smooth trees), fol- 

 lowed closely by cloth (85.1 per cent of smooth trees). The cloth wrap- 

 ping, however, shows the highest percentage of smooth trees per 100 

 grafts planted when not only the crown-gall but also the hairy-root 

 are considered. The difference is very slight, however. The other 

 wrappings show less favorable results, least of all in the case of the 

 grafts wrapped with plain thread and covered with grafting wax (44.2 

 per cent of smooth trees), followed closely by those with no wrapping 

 whatever (54.8 per cent of smooth trees). 



RECOMMENDATIONS. 



From the results so far obtained, the use of either cloth or rubber as 

 material for wrapping apple grafts is recommended. Owing to the 

 expense involved in the use of rubber, cloth will be found the most 

 desirable, and in most cases will probably give results fully as satisfac- 



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