PEACHES 161 



they are touched or jarred they let go "all 

 holts" and tumble to the ground. 



Like all fruit trees the peach is attacked by 

 several scale insects all of which yield to the 

 same treatment — a winter spray with commer- 

 cial lime sulphur solution. 



The most talked-of and the least important 

 disease of the peach is the "yellows," which 

 I have already mentioned. Specialists have 

 worked on it for thirty or forty years and the 

 sum total of their knowledge to-day is that it 

 is a "physiological" disease — meaning that 

 they do not know what it is. My own opinion 

 for many years was that it was closely related 

 to winter injury of some sort. I am still in- 

 clined to think that this is true in spite of the 

 fact that it failed to make an appearance after 

 the severe winter of 1917 when many trees were 

 killed outright. It is characterized by a yel- 

 lowing of the leaves, spotting of the skin and 

 streaking of the flesh of the fruit with red and 

 by the development of many clusters of slender 

 wiry twigs. The yellow leaves may result from 

 other causes, but when the disorder progresses 

 to the point where the twig clusters are formed 

 the tree should be taken out and burned. The 

 disease is claimed by some to be contagious. 

 Maybe it is. At any rate we can play safe by 

 burning affected trees and maybe some day 

 some one will learn just what causes the 

 disease. 



