DISEASES OF CROPS 



207 



Treatment. Same as for yellows. 



Peach Rosette. The cause of this disease of the peach in the Southern 

 states is also unknown. It is very similar to yellows, but the leaves tend to 

 cluster, giving the general appearance of green roses. 



Treatment. Same as for yellows. 



SPRAY TABLE FOR PEACH. 



5. Same as 2 for very late varieties. 



NOTE. Arsenical poisons may be added to No. 2 for curculio. Tobacco extracts and soap can also be added for suck- 

 ing insects. 



PLUM 



Black Knot (Plowrightia morbosa [Schw.], Sacc.). This very common 



and well-known dis- 

 ease causes swollen 

 growths on the 



^S^fe jflKH^ branches which are 



jm at first olivaceous in 



color, but finally be- 

 come deep black and 

 very hard and brit- 



^^/ tie. It will spread 



over the greater part 

 of a tree, interfere 

 with its growth and 

 finally cause its 

 death. 



Treatment. 

 The diseased parts 

 should be cut out 

 and burned and the 

 trees should be 

 sprayed with lime- 



BLACK KNOT ON THE CHERRY. 1 

 Photograph by Prof. J. P. Helyar. 



sulphur in the spring 

 before the opening 

 of the buds. (See 

 table for plum.) 



Leaf Spot. See Cherry. Mildew. See Cherry. Yellows. See 

 Peach. Brown Rot. See Peach. Crown Gall. See Apple, 



Courtesy of New Jersey Agricultural Experiment Station, 



