black stain and small slice wound on oak tree
looks like tree blew small slit open and oozed black tar out. What could this be and what to do?
Lincoln County South Dakota trees and shrubs
This may be a bleeding canker disease. There are bacterial and fungal organisms that can cause this problem. Knowing the tree species can help determine which plant pathogen it is. I would recommend you contact your local Iniversisty Extension office for further information on this problem. A sample may be taken and disease organism diagnosed through your Univeristy Extension Plant Pathology lab.
Paula Dinius, Urban Horticulturist