1558 



ENCYCLOPEDIA OP PRACTICAL HORTICULTURE 



be inefcted. Fortunately, only a few 

 branches become infested in this way and 

 the majority of these die before the next 

 spring, leaving only a very small per- 

 centage of the infection caused by this 

 method even in serious cases. 



Control 



Since the great majority of infections 

 take place at the time the buds open in 

 the spring, from spores adhering over 

 winter to the bud scales and twigs, it is 

 obvious that a spray that will kill the 

 spores or prevent their germination, ap- 



Fig. 1. Peach Leaves Affected with the Fungus 

 Causing Peach Leaf Curl. Note the wrinkled 

 and distorted tissues. 



plied early in the spring before the buds 

 open, will control the disease. 



Use the Bordeaux mixture, 5-5-50, or 

 the lime-sulphur 30-degree Beaume, di- 

 luted 1-15, and apply early in the spring 

 just before or while the buds are swell- 

 ing, but before any of the buds show any 

 green. If any of the buds show even 

 the green tips of the leaves, they may 

 become infected. 



Spraying will not prevent infection 

 resulting from the mycelium wintering 

 over in the bark of twigs. Fortunately 

 this method of wintering over accounts 



for only a small proportion of the infec- 

 tion. 



In spraying for leaf curl it is impor- 

 tant that every twig be thoroughly cov- 

 ered with the spray. 



The general experience of investigators 

 has shown that either of the sprays men- 

 tioned are equally good in preventing 

 this disease. Experiments carried out 

 by the Department of Plant Pathology 

 in the spring of 1910 confirm the results 

 of these investigators. Prom observa- 

 tions made during the spring of 1912 it 

 would seem that the growers had more 

 uniform success when the Bordeaux mix 

 ture was used. 



Peach Shot Hole 



Gercospora circumscissa Sacc. 

 The effects of this disease resemble 

 those caused by Cylindrosporium of the 

 plum. The diseased spots fall out, and 

 the small branches are also attacked, of- 

 ten causing a great number of the young 

 shoot to diet. Spray with lime-sulphur, 

 as for peach leaf curl. 



R. D. Whitmarsh, 



Amherst, Mass. 



Powdery Mildew 



Sphaerotheca pannosa 

 Podosphaera oxycanthae 



H. S. Jackson 

 Powdery mildew is not an uncom- 

 mon trouble on peaches, though sel- 



Fig. 1. Powdery Mildew on Fruit of Peach. 



