APPLE GROWING 



as they appear. The same Is true of other 

 caterpillars and leaf eating worms. Apple tree 

 borers are frequently serious, especially In 

 young orchards, where the trees should be regu- 

 larly " grubbed " and the borers dug out or 

 killed with a piece of wire. They may be 

 prevented to some extent by painting the tree 

 trunks with a heavy lime and sulphur or some 

 gas tar preparation. 



Diseases. — Although not as numerous as 

 Insects, the diseases which attack the apple in- 

 flict great damage and are fully as difficult to 

 control. They are caused by bacteria and by 

 fungi which may be compared to weeds growing 

 on or In the tree instead of the soil. If either 

 of these works within the plant, as Is sometimes 

 the case. It must be attacked before It enters. 

 It is very necessary to be thorough in order 

 to control these diseases. Weather conditions 

 influence nearly all of them materially. Of 

 those which attack the apple tree or fruit we 

 have selected three as the most serious and the 

 most necessary for the grower to combat, 

 namely, (i) apple scab, (2) New York apple 

 tree canker, and (3) fire blight. To these 

 should be added In the South and middle lati- 

 tudes, sooty blotch and bitter rot. Baldwin 

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