( Pseudomonas monsprunorum )
Affects members of the Prunus Genera - plum, cherry, apricot. A swollen area on the bark exudes a light brown gum, usually near the angle of branches. If the swelling encircles the branch it is killed. Wind or water-borne bacteria enter leaf scars and pruning wounds during the autumn. Young leaves can be infected in May or June, a brown spot about 2mm accross develops, the dead tissue falls out leaving a hole - "shot hole".
Some varieties of Prunus are resistant. Infected branches should be pruned out and burnt.
Arbrex wound paint can be applied to pruning scars. An autumn spray of Bordeaux Mixture may prevent infection.
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