38 STATE POMOLOGICAL SOCIETY. 



lip on the margin as in the case of canker or a mechanical wound 

 the new living tissue is forced with thinned out edges between 

 the wood and the dead bark. Patches like these offer an excel- 

 lent opportunity for the entrance of fungi. In fact those 

 formed last winter show today almost without exception more 

 or less infection and if one has not followed the history of the 

 case there is considerable chance of being misled as to the cause. 

 The natural inference would be that the fungi are the original 

 and only causes of the dead areas. However, if the fungi are 

 allowed to develop they may eventually cause the final destruc- 

 tion of the trees, therefore, prompt remedial measures should be 

 taken. As soon as the frost patches are apparent in the 

 spring the bark should be cut away till the healthy margins are 

 exposed and the wound covered with a coat of white lead or 

 thin grafting wax. In an orchard where this has not been done 

 I would now wait until just about the time growth begins in the 

 spring and make a pretty thorough job of getting rid of all 

 tissues which show signs of decay. 



There is some difference of opinion as to how severe pruning 

 we should do on badly injured trees. Personally I think I 

 would prune rather sparingly the first season but during the next 

 winter or early spring I would cut out all dead wood going well 

 back on the living tissues, to be sure that all infesting fungi are 

 removed. Of course, this dead wood should at once be burned 

 to destroy the fungi contained therein. In many cases top 

 grafting may be used to advantage. 



In the history of Maine orcharding we probably have had no 

 other single season in which so many fruit trees were killed as 

 in the winter of 1906-7. This was due, as I shall attempt to 

 show, to the severity of the weather and the abrupt fluctuation 

 of temperature from extreme cold to thawing. However, we 

 have good reason to believe that many trees were more suscep- 

 tible on account of not having fully recovered from the freezing 

 of 1903-4 and 1904-5, for I find the following statement from 

 Professor Munson's pen: "The winters of 1903-4 and 1904-5 

 were exceptionally severe in Maine, and as a result many com- 

 plaints were made that the a])ple orchards had suffered more 

 than for the previous 20 years." 



The injurious effects of a winter like that of 1906-7 are more 

 easily understood if we know something of the structure of a, 



