84 



Diseases of Economic Plants 



Self-boiled lime-sulfur, 8-8-50, applied as indicated for 

 peach brown-rot, gives excellent results. 



-Curl 9^ (Taphrina deformans (Fcl.) Tul.).* — Throughout 

 the peach-producing region this disease abounds, being par- 

 ticularly injurious in moist localities. The annual loss 

 approximates $3,000,000 in the United States. 



Curl is due to a fungus which grows in the leaves, causing 

 the peculiar malformation which justly gives rise to its 



Fig. 43. — Peach leaf-cui 



\tkinson. 



popular name. This fungus destroys the utility of the leaf 

 as a starch-producing organ, and eventually causes defolia- 

 tion. This loss may be manifest in two ways: first, by the 

 present effect upon the vitality and vigor of the tree, and 

 immediate injury to the crop; second, by a weakening of the 

 tree in succeeding years, due to the lack of full nourishment 



* The sub-genus Exoascus is by some regarded as of specific rank and 

 the name as Exoascus deformans. 



