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treea ia the spring, becoming evident as areas of discolored 

 bark which spread until mid-summer and then produce pycnidia. 

 In some cases the disease completely girdles the limb cut- 

 ting off the flow of sap, which causes the leaves to shrivel 

 up and die. The spores lodge in wounded places on the sur- 

 face of the bark. A geirai tube is sent out which under fav- 

 orable conditions grows and produces a branched mycelium 

 on which pycnidia are formed in about one month, and more 

 produced as the mycelium grows and branches. These pycnidia 

 contain thousands of spores imbedded in a gelatinous mass inside 

 the pycnidium, and as water enters they sweel end. the spores 

 are shot out, blown about by the wind, and those that fall 

 and germinate in a wound produce the cankers. The mycelium 

 seem to be unable to penetrate to the cambium through living 

 bark, which would suggest a means of control; namely, to 

 avoid wounding the bark. 



All wounds should be coated with thick paint or graft- 

 ing wax. Cankered limbs should be cut out wherever practi- 

 cable, and as a further precaution, thorough spraying with 

 lime sulphur applying 6 to 8 gallons per tree as follows: 



1. When the petals begin to separate and the first 

 tinge of pink begins to show. 



2. When about two-thirds of the petals have fallen. 



3. As soon as all the blossoms have fallen, 



4. Ten days or two weeks after No. 3. 



These two fungous diseases are by no means the only 

 ones which affect the apple, but perhaps they are the most 

 inDortant of any of them. 



