142 THE AMERICAN PEACH ORCHARD 



The cost of this treatment will vary from three to lo 

 cents a tree, five cents being a fair average for medium- 

 sized trees under usual labor conditions. A very 

 slight increase in the crop will pay handsomely for 

 this investment. 



SCAB 



Taking it the country over, scab stands next to 

 the brown rot as destructive peach fungus. The dis- 

 ease is common throughout all the peach-growing 

 districts, at least to the east of the Rocky Mountains. 

 It is present in nearly all orchards, and especially 

 in wet seasons causes enormous damage. It is more 

 common in the central and southern states than in 

 the northeastern states. 



This disease, known also as spot and sometimes 

 as mildew, is caused by a fungus which occurs in the 

 skin of the peach. It produces small, rough, black 

 spots which give the fruit a smutty appearance and 

 which usually cause the skin to crack open in a very 

 unsightly fashion. The fruit is stunted in size and 

 remains hard and tasteless instead of ripening prop- 

 erly. The fungus also attacks the twigs. 



Different varieties vary greatly in their suscep- 

 tibility to the attacks of peach scab. Late varieties 

 usually show the disease worse than early varieties. 

 Those sorts which are commonly grown in the cen- 

 tral states — Delaware, Maryland, Pennsylvania, 

 West Virginia — seem to be more subject to damage 

 than the varieties which are popular northward, 

 such as Greensboro, Carman, Champion, etc. 



Early sprayings with Bordeaux mixture or other 

 fungicides tend to prevent this disease by killing the 

 spores and preventing early infections. The most 

 practicable treatment, however, seems to be that 

 recommended by Scott and Quaintance and already 

 outlined under the head of brown rot. 



