Symptoms 



due to Nectria ditissima. Out out cankered 

 spots and paint wounds (5) ; attend well to 

 drainage and destroy wooUy aphis (p. 122). 

 Other fungi produce canker ; treat in same way. 



Young branches cracked, and with olive- 

 green areas upon them. Scab (see fruit, below). 



Young branches cracked, twigs and spurs 

 dying, and bearing small grey mounds of fungus 

 mycelium and spores. Brown rot (see fruit, 

 below). 



Foliage. — Dark branching mycelium on 

 leaves, followed by dead spots. Scab (see fruit, 

 below). 



Rounded brown spots with a dark margin 

 and bearing minute black dots on upper surface. 

 Leaf-spot. Cladosporium herbarum. Attend to 

 health of tree ; spray with Bordeaux mixture (7). 

 Sphaeropsis malorum also forms similar spots 

 (and cankers on stem), and is treated similarly. 



The whole leaf covered with a white powdery 

 mildew which also involves the shoot. The 

 myceUum subsequently forms a felted mat on 

 the shoot, which becomes very weak and often 

 dies. Conspicuous, owing to grey colour in 

 winter. Prune off and burn as soon as seen, 

 below the point of attack (3). Some varieties 

 are much more prone to attack than others, 

 e.g. " Bismarck," " Lord Grosvenor," " Irish 

 Peach." Caused by Podosphaera leucotricha. 

 67 



