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GLEANINGS IN BEE CULTURE 



Pear blii^ht entered the growing tips of tlie blossom. 



PEAR BLIGHT OR FIRE BLIGHT 



BY DR. H. A. SURFACE 



During the jjresent year there is an un- 

 usual manifestation of pear blight or fire 

 blight on apple, pear, and quince trees, 

 from the Mississippi River to the Atlantic 

 Ocean, and from the central portions of 

 Illinois, Indiana, Ohio, and Pennsylvania, 

 southward to .Alabama. 



This disease makes itself manifest by the 

 death of the leaves, fruit, and bark of the 

 infected apple, pear, and quince trees. It 

 is given various names such as pear blight, 

 fire bliglit, leaf blight, black blight, black 

 twig, black llag, black leaf, twig bliglit, 

 canker blight, body blight, bark bliglit, 

 trunk blight, collar blight, and collar rot. 

 In the last-named form it is by all means 

 the most serious and destructive enemy of 

 our fruit-trees because it worlvs around the 

 collar and roots of the trees, and cannot be 

 headed oft' nor cured; and when it girdles 

 the tree the latter dies. 



This is a bacterial disease that enters 

 tlirough the tips of growing shoots or 

 through blossoms, or througli any part of a 

 living leaf, fruit, stem, twig, or bark that 

 may be injured by the puncture of an 

 insect or otherwise lliat will thus permit the 

 entrance of blight germs. When the germs 



once get inside the bark they spread both 

 upward and downward through the cam- 

 bium or growing layer, and cause the bark 

 to turn black and the wood to become brit- 

 tle, A blighted twig is often seen broken 

 and hanging downward. 



. The bacterial germs spread much more 

 lapidly in fruit-trees that have grown rank- 

 ly. Tliis is doubtless because the wood is 

 inore porous and tlie sap ducts are large)", 

 a)id admit the passage of the germ more 

 I'eadilj^ in the pores of thickly grown wood. 

 It is conspicuously true that wherever trees 

 are grown in very fertile soil, or have been 

 fertilized with barnyard manure or othei- 

 nitrogen fertilizer, or have been cultivated 

 considerably to make them grow, there, as a 

 j'ule, the blight is greatest this year. Tliis 

 means that foi' these trees that are subject 

 to blight it is best for the orchardist to prac- 

 tice such methods as will reduce the amount 

 of vigorous groAvth. Among these are light 

 summer pruning, seeding down with a cover 

 crop like crimson clover or rye, avoiding 

 r'ultivation and nitrogen fertilizei-s, and 

 applying only fertilizers containing i)hos- 

 phorie acid and potash if any. 



Unfortunately tlie onlv real remedy that 



