LUTHER BURBANK 



germs to other trees and to flowers and fruit even 

 fairly remote is thus assured. Not merely flies and 

 gnats, but the bee itself may have a share in thus 

 transporting the contagion from one tree to 

 another till it infects every tree in the orchard. 



The nectary of a pear, which the bee may in- 

 advertently inoculate, furnishes a most favorable 

 medium for the multiplication of the bacilli. 

 Thence they work their way from the fruit buds 

 to the limbs. Once they gain access, through the 

 links in the tree's armor furnished by the buds, 

 to the cambium layer of the inner bark, there is 

 nothing to prevent the indefinite extension of their 

 colony. 



A tree thus inoculated may soon take on the 

 appearance of a tree scourged by fire. Indeed, 

 the malady is sometimes spoken of as "fire blight." 

 ANTISEPTIC SURGERY IN THE ORCHARD 



The measures taken by the horticulturist to 

 save his tree when thus attacked are curiously 

 suggestive of the methods of the modern surgeon. 

 Infected limbs must be amputated; local areas of 

 infection in the bark or trunk or large branches 

 must be thoroughly excised, including a goodly 

 portion of healthy wood and bark to make sure 

 of the removal of every microbe. Large wounds 

 are then carefully disinfected with a sponge or 

 bunch of waste soaked in kerosene or in a solu- 



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