SEVENTEENTH ANNUAL MEETING. 6l 



Symptoms. 



The most reliable symptom of peach yellows is the pre- 

 mature red spotted fruit. Another sympton almost equally 

 certain is the bushy or wiry twig growth often resulting from 

 premature pushing of lateral buds. Diseased trees, more or 

 less, promptly assume a sickly or yellow color in their foliage. 

 The leaves often have a peculiar roll and droop. After the 

 second year the twigs and branches begin to die back and the 

 tree gradually dies from the top down, ordinarily becoming 

 totally dead at four or five years from the appearance of the 

 first visible symptom. The symptoms may be discussed more 

 critically by taking up the behavior of the different parts of 

 the tree. 



The Fruit. On trees first attacked, the fruit usually 

 ripens a week or ten days ahead of time, sometimes even two 

 weeks or more. It is generally oversized, being actually larg- 

 er than normal fruits of the same variety on adjoining trees. 

 The red spotting may be very pronounced, and more or less 

 red coloration accompanies it, aside from the spots. Inside 

 the peach, the flesh is found to be filled with reddened veins. 

 On some varieties naturally red, such as the Triumph, the 

 whole flesh, or parts of it, may become blood red. The red 

 spots on the skin or the red flecks in the flesh occur in vary- 

 ing degrees of prominence. Sometimes there is scarcely any 

 red spotting on the fruit plainly premature and undoubtedly 

 from a yellows tree. The writer noticed some Smock trees in 

 Pennsylvania last fall. Though plainly affected with the yel- 

 lows, many of the fruits showed little or no red spotting and 

 red veins. Varieties like the Gold Drop may be premature 

 without much, if any, reddening. The disease then, stimulates 

 the formation of red coloring matter, though it is not always 

 able to produce it. Usually the fruit tastes bitter and flat. 

 The premature red spotting of the fruit is the most reliable 

 symptom of the peach yellows. Yet even this symptom can- 

 not be taken absolutely, inasmuch as girdling, either mechan- 

 ical or by frost injury, produces a somewhat similar result- 

 Prematuring by girdling and frost injury, however, can gen- 



