INSECTS AND DISPOSES OF THE PEACJI 1107 



galls grow to be as large as two inches in diameter. Nursery stock 

 is occasionally found badly infested, although the disease does not 

 seem to lie seriously contagious in this state. The galls are soft 

 and spongy and are generally situated at the crown or on the large 

 roots. Trees affected with galls should not be planted unless the 

 galls can be cut off without too much loss of roots. 



Powdery Mildew 



This fungous disease (Sphcerotlieca pannosa [Wallr.] Lev.) 

 lives for the most part on the surface *of the plant, sending its 

 r-ootlike hostoria into the cells of the host to take up its nourish- 

 ment. The light gray growth is the fungus itself. It often at- 

 tacks young trees in the orchard during the first, second, and third 

 years growth, especially when the trees are on rather low wet 

 i: round. Old trees that have been severely dehorned and forced 

 into rapid growth. are subject to mildew particularly when growth 

 is thick and compact. The fungus takes the sap out of the leaves, 

 thereby checking the growth and causing the foliage to turn a 

 grayish brown. The edges of the leaves may roll, gradually dry, 

 and crack. Powdery mildew is common in western New York 

 orchards. 



Control. Growers do not practice using spray to control this 

 disease of the peach. The trees affected are usually young and 

 nonbearing, and have grown sufficiently for the season by the time 

 the fungus appears. It is not usually necessary to spray for the 

 powdery mildew on the peach. 



Peach Spot, or Scab 



Peach spot, or scab, (Cladosporium carpophilum Thum.), is a 

 very common disease in this state. In years when rainfall is heavy 

 during the summer season, it is favorable for the disease. Usually 

 the infection occurs during the latter half of July or the first half 

 of August, taking place on the side of the peach that lies upper- 

 most. Many varieties, such as Carman, Champion, Yellow St. 

 John, Elberta, Salway, and Hills Chili are susceptible, but Yellow 

 St. John, Salway, and Hills Chili are invariably so. 



Control. The disease is not common since the use of bordeaux 

 mixture has been discontinued to make a spraying for peach scab. 

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