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The Fruit Spot that can be controlled by July spraying is 

 characterized by numerous small spots, about 1-16 of an inch across, 

 that are at first deeper green or red than the surrounding color ; 

 and soon becomes dead, and brown or black. The flesh is not af- 

 fected deeply. They are more numerous towards the apex of the 

 fruit, and frequently occur at lenticels. The cause of this fruit 

 spot is the fungus Cylindrosporium pomi, which infects the fruit 

 during July as a rule, and can be readily prevented by one or two 

 applications of almost any fungicide during the first half of July. 

 We must not confuse this disease with that known as Fruit Pit 

 which seems not to be due to fungus attack, and can not be con- 

 trolled by spraying. 



Let us remember that the requirement for summer spraying, 

 as for any spraying, and the returns to be obtained from it, depend 

 on the presence of certain fungi that develop then, the growing of 

 varieties susceptible to their attack, and the occurrence of weather 

 conditions that would favor their development ; and that the most 

 satisfactory results will be obtained when judicious spraying is an 

 adjunct to the use of good methods of culture and sanitation. 

 Spraying is, after all, an expedient to catch, as it were, the thief 

 after he is in the house. Let us see to it that we do not allow ways 

 to multiply by which he may enter. 



There are certain transmissible diseases that can not be satis- 

 factorily controlled by spraying, such as Twig Blight, and the 

 cankers produced by the Black Rot and Bitter Rot fungi, and the 

 several wood rots and root rots. Our only means of holding these 

 in check is to discover the trouble at an early period in its develop- 

 ment, and thoroughly remove all affected tissue. 



Twig Blight, sometimes known as Fire Blight, attacks young 

 shoots, the bark of older limbs, and sometimes the blossoms or 

 young fruit. As soon as blighted twigs are noticed, they should 

 be cut off well below the affected part and the cut surface, how- 

 ever small, touched with a swab wet with a disinfectant, such as 

 I to 1000 bichloride of mercury ; tools also should be wiped with 

 such a solution at frequent intervals. Cankers can frequently be 

 cut out ; but often the affected part must be sacrificed. Large cuts 

 should be painted over as well as disinfected. 



Collar Rot as we find it causing the death of the bark at the 

 base of the trunk of apple trees, is a perplexing condition. I am 

 not satisfied as to its causation in every case. Perhaps we ought 

 to bear in mind that this part of the tree is the one where general 

 decay is most likely to occur because moisture from the soil and 

 a good oxygen supply favor general decay organisms. We know 

 that a fence post will usually rot because of the same conditions, 

 more rapidly near the surface of the ground than above or below. 

 I am sure that in some cases winter injury is primarily responsible 

 for the trouble with the apple trees. In a few instances I have 

 found the Blight bacterium present as the cause of the extensive 

 death of the bark; and I have also found other organisms associated 

 with the trouble, such as the fungus of Black Rot, the wood rotting 

 Schizophyllum, and the root rotting Armillaria. In the far west, 

 some hold that arsenic injurv to bark is responsible for a somewhat 



