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Acer tar spot

Symptoms

An outbreak of shiny black blotches, edged in a ring of yellow, disfigure acer leaves in early summer. This can lead them to fall prematurely.
Find it on: acers
Time to act: early summer

Overview

The fungus Rhytisma acerinum overwinters on fallen acer leaves, then infects the new spring foliage. The first signs are yellow leaf spots that turn into large shiny black blotches up to 1.5cm across. Severe cases can mean the leaves drop early, but the health of the tree won't suffer.
Solution
An outbreak of shiny black blotches, edged in a ring of yellow, disfigure acer leaves in early summer. This can lead them to fall prematurely.
Organic
Rake up and dispose of all fallen infected leaves.
Chemical
As a preventative measure use a recommended fungicide, containing either a Bordeaux mixture or copper, and spray before signs of infection and repeat at 10-15 day intervals.


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Talkback: Acer tar spot
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Ekybor-0 24/11/2011 at 15:29

I have had difficulty finding the recommended fungacide even at reputable garden centres