THE BEACH PLUM 



13 



Brown rot, a \er\' common disease 

 of peaches, cherries, and plums, is 

 caused by the fungus Monilinia jruc 

 ticola, which sometimes causes severe 

 loss in one of several ways. It ma\' 

 infect (1) the blossoms, preventing 

 the set of fruit (called "blossom 

 blight"); (2) the twigs (called "twig 

 blight); (3) large limbs, causing 

 cankers; or (4) green or ripe fruit, 

 especially where it has been injured 

 by insects, causing it to rot. These 

 (leca\ed fruits dry, shri\"el, and be- 

 come mummies covered with a gray 

 molfl from which spores are liberated 

 to infect other fruits. Depending on 

 conditions, these mummies may hang 

 to the tree. In these mummies and in 



^ '* 





Figure 14. Leaves Affected with the 

 Shot Hole Disease. 



Photo courtesy of Plant Pathology 

 Department, Cornell University. 



Figure 13. Tvpical Brown Rot Mummy of 



Plum 

 The disease Hves over winter in these 

 mummies and in limb cankers. 



the limb cankers the fungus winters 

 over. Brown rot is fairly eas\- to 

 control by spraying thoroughly with 

 wettable sulfur. 



Leaf spot, or shot hole, caused bv 

 the fungus Coccomyces prunophorae, 

 is a xevy common disease of beach 

 plums. It produces on the leaves 

 round or irregular reddish or purplish 

 spots which may turn brown and drop 

 out, giving the leaves the appearance 

 of having been peppered with shot. 

 This disease ordinarily attacks the 

 fruit very little. The damage to the 

 leaves, which sometimes turn yellow 

 and drop, may weaken the bushes to 

 a considerable degree. It can be con- 

 trolled by applying sulfur sprays. 



