Q.Walnut trees sick with Canker disease
I have a black walnut tree that is easily 100 yrs old since this whole area used to be walnut orchards. The tree looks like, at one point, it was cut down but then 4 separate trunks grew back around the outer edges of the stump. It currently has what appears to be a large open wound with orange pus-like sap dripping out.
We have had 2 tree guys out who both say it is canker disease and the tree just needs trimmed but I am still concerned. We also have an English walnut that is about 40 feet away from the black walnut that is leaking the orange sap as well as dripping clear sap from several branches on the tree.
We have not trimmed recently. Both trees are currently leafless, as we are in late winter. I live in the bay area of Northern CA. What can/should I do? Please help! Thank you!
I would agree with the tree advice you have all ready received. You need to cut back the affected areas, to prevent spreading of the Canker.
Here is an excellent article that will help you.
https://www.gardeningknowhow.com/ornamental/trees/tgen/cankers-on-trees.htm