BBUPACEOUS FRUITS 119 



Brown rot, mold (Sderotinia fructigena (Peru.) Schroet.). — 

 The same fungus which produces disastrous results upon 

 the peach also causes rot of the cherry. Several stages 

 of its development are illustrated in Fig. 52. The dis- 

 ease is known practically ever>^where the cherry is grown, 

 and large losses are frequent. Fifty per cent loss was re- 

 ported from New York, and 25 per cent from Missouri. 

 Treatment is the same as for the peach. 



Yellows. See peach. 



Curl {Exoascus Cerasi Fckl.). — The cherry curl is closely 

 related to that of the peach. The leaves become wrinkled 

 before they are full size, and spores are produced on the 

 surface of the leaf, as they are in other curls. Instead of 

 forming flower buds and spurs, affected regions develop a 

 profusion of t\vigs, " ^vitches' brooms." The disease is 

 not common in America; but should it become so, it can 

 be held in check by pruning out the diseased twigs. It is 

 perennial in the t^vigs and should be avoided in budding 

 and grafting. 



Scab. See peach. 



Powdery mildew {Podosphcera Oxijcanthce (DC.) DeBy.). 

 • — This mildew, described in connection with the apple dis- 

 eases, sometimes does damage to the plum and cherry, 

 especially on nursery stock, where it prevents either the 

 growth of the seedUng or successful budding or grafting. 



On old leaves the disease does not cause great damage, 

 but when the attack is made on young growing tips, or on 

 young leaves, these delicate structures suffer greatly from 

 loss of nourishment. 



Contrary to the nature of most fungous diseases the mil- 

 dew grows best during fair, dry weather. A light rain, 



