56 STATE POMOI.OGICAI, SOCIETY. 



begins ^o appear some seasons very early, even while the apples 

 are in bud, and may come at various times during the season. 

 The scabby spots on this fruit nearly all came after the fruit 

 was quite well grown, perhaps larger than half size. This apple 

 scab is thoroughly preventable by spraying with Bordeaux 

 mixture. 



We are sending you Farmers' Bulletin No. 243 on Fungicides 

 and Their Use in Preventing Diseases of Fruits, which will give 

 you the methods of making and applying this mixture. On page 

 18 * you will find a very brief discussion of the treatment for 

 apple scab. The treatment there outlined is supposed to cover 

 the disease when at its worst. Possibly you might be able to 

 leave out some of the early treatments if you could count on the 

 fungus behaving another year as it did the past season. I am 

 not at all sure, however, that you will be safe in making that 

 assumption. 



Now these apples are also affected by a fungus rot which has 

 come into the fruit after it was picked. The apples look as if 

 they had been oveheated, either in the pile in a warm spell in 

 October, or in the bins where stored, or possibly in the barrels ; 

 at any rate, a rot fungus purely secondary to the original trouble 

 has entered the scab spots and is the principal cause at the 

 present time of the rotten and demoralized condition of these 

 apples. By examining the fruit again, you will see that some 

 of the scab spots have no rot around them, and have remained 

 straight apple scab ; other scab spots have a brown rotten area 



* The formula here referred to is of a Bordeaux mixture made of the following in- 

 gredients and is known as the 5-5-50 formula: 



Copper sulphate pounds . . 5 



Lime do ... . 5 



Water to make gallons . . 50 



The use of this formula is desirable where the purity of the lime is in doubt, as it makes 

 certain, with lime of any reasonable quality, that all of the copper is properly neutralized. 

 The danger of scorching or russeting the fruit is therefore less. Withholding 1 pound 

 of copper sulphate also cheapens the mixture by a few cents. For these reasons the 5-5-50 

 formula has come to be quite generally used in orchard spraying. In fact, it has almost 

 replaced the old standard Bordeaux mixture in spraying for the apple scab, bitter rot, 

 pear and cherry leaf-blight, and similar diseases. In the central Mississippi valley the 

 4-5-50 formula has given good results, especially in dry years. 



For scab, spray with either of the mixtures as follows: 



First, when the cluster buds have opened and exposed the flower buds; second, just 

 after the petals have fallen; third, a week or ten days later; and fourth, two weeks after 

 the third spraying. In a rainy season this disease is rather difficult to control and may 

 require five or six applications. In case of a dry spring, however, only three appli- 

 cations are usually repuired. 



