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The Fruit-Growers Guide-Book 



known 1o attack the plum. It is known by a variety of 

 names, such as twig blight, fire blight, blossom blight, etc. 

 It is a bacterial disease, the organisms working entirely 

 within the host, where it cannot be reached by any spray 

 or wash that may be applied. 



Body of pear tree infected with blight through the care- 

 less removal of a limb. Pruning tools should be sterilized, 

 likewise the wounds, and then covered with paint, wax or 

 tanglefoot. 



The disease usually appears on trees at just the time 

 they are in bloom, as the organisms causing the disease 

 are carried from tree to tree by the bees and other insects 

 which visit the flowers. They may also be transported by 

 numerous kinds of leaf feeding insects and thus be carried 

 to the twigs of many trees which are not in bloom. When 



