414 



PLANT DISEASES 



the fungus is absolutely necessary for its perpetuation, and as 

 the disease is not known to appear on other plants than the apple 

 and the cedar a remedy naturally suggests itself, namely that of 

 destroying all cedar trees in the vicinity of the apple orchard. In 

 fact, no other satisfactory remedy for the control of the disease 

 has yet been devised. Legislation has been enacted in some states 

 to require the cutting of cedar trees in the vicinity of commercial 

 orchards. 



Brown Rot. This is probably the worst disease of the stone 

 fruits, attacking the leaves and fruit of peaches, plums, cherries 



Fia. 288. Manilla (brown rot) of peach showing the attacks on fruit and twigs. Plums 

 and cherries are likewise affected. (New Jersey Station.) 



and their allies (Fig. 288). The leaves turn brown or are otherwise 

 discolored, and ripening fruit rots on the trees. Many of the fruits 

 at this time prematurely drop to the ground. Others cling to the 

 trees, and if not picked will later dry up and become mummified, 

 in which condition they are often seen after the leaves fall. 



Spray the trees while in their dormant condition with lime- 

 sulfur (1-40). A second application is made just after the blossoms 

 fall. With the peach, this is when the shucks are shed from the 

 young fruit. A third spraying is given about ten days or two 

 weeks later. Poison is usually mixed with these materials for the 



