Ash Dieback is a disease which is caused by the invasive fungus Hymenoscyphus fraxineus. It is very likely that the fungus reached Europe through the international plant trade, since studies have shown that it lives peacefully on Asian ash species without harming them. Usually, the fungus is invisible to the eye, but during the winter it forms white fruiting bodies on dead branches on the forest floor.
Today, there is no known cure or protection against Ash Dieback, but if one would try to protect a single ash, one can remove dead branches below it to keep the fungus from hibernating there.
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