On my cherry-trees I observed that the leaves of the tips of newly grown branches are wrinkled and inside there is something which simply said looks like black dirt. The leaves do not look damaged, only their form has suffered,
It seems that only tips are affected which are not higher than 1.5 to 2m from the ground.
Additionally I saw that several ants where walking on the branches.
Is this a pest? Could it be an ant-tribe which is farming? Do I need to do something?
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