Marin Master Gardeners
University of California
Marin Master Gardeners

Do the Leaves on Your Trees Look Scorched?

Blackened Fruit
Blackened Fruit

In our drought, you might think those "scorched" leaves and blackened fruit are the result of lack of water.  However, the culprit may be a case of fireblight, caused by an infection by

Tree Branches infected with Fireblight
Tree Branches infected with Fireblight


Erwinia amylovora
, a bacterium that frequently affects pome trees, such as apples, pears, and also crabapple, Pyracantha, quince, cotoneaster, hawthorn, and toyon. Signs include a sudden wilting, shriveling, and blackening of shoots, flowers and fruit, making them appear "scorched". Mild temperatures (65- 85F) and intermittent rain, are perfect conditions. Here's more about fireblight and how to spot and manage fireblight

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