Tree Fungicide - How can I treat it??

Asked March 6, 2020, 5:43 PM EST

I have attached 3 pictures of my neighbors tree (species unknown) that has an advanced stage of fungus on many of its branches. This same fungus has now invaded my purple leaf plum - less severe than attached pics, and I am concerned about how to combat it - treat/save the tree. Thank You!

Anne Arundel County Maryland

1 Response

This looks like black knot fungus on the branches. It is a disease of plants in the Prunus genus (plum, cherry, etc.). It can affect edible and ornamental plum trees alike.
https://extension.umd.edu/hgic/topics/black-knot-trees

Chemical controls for black knot are not very effective once the black galls are present. You can prune out infected stems and branches 4 to 6 inches below the galls and remove the clippings from the landscape. If the disease has progressed too far in the tree, you may have to consider replacement.

Marian