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Lilac tree blight? #878865

Asked July 26, 2024, 11:04 AM EDT

My lilac tree, at least 25 years old, has developed what I think is blight (from looking at photos). It has never had problems before but of course this season has been extremely wet. Large portions of the leaves are rusty or very dark, appear dead and curled under, but the leaves at the tips of the branches are still healthy looking. Can the tree recover on its own? Are there things I should do to help it? Thank you!

Hennepin County Minnesota

Expert Response

Hi,

Many lilacs are getting bacterial blight this year. Here's some helpful web pages:

https://yardandgarden.extension.iastate.edu/encyclopedia/lilac-bacterial-blight

http://plantclinic.cornell.edu/factsheets/lilacbacterialblight.pdf

If you don't think this is blight, this page may help you narrow the cause:

https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/lilac/

The only way to determine if this is blight is to have a sample of the plant tested. The Plant Disease Clinic at the U of M does this, but for a price. You can find more information here:

https://pdc.umn.edu/

Both of the links above suggest ways to manage the disease, including raking up and disposing of fallen leaves and pruning to open up the plants and allow better air circulation.

Good luck.

MJ Replied July 26, 2024, 9:34 PM EDT

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