Q.Do You Recognise This Oak Tree Condition?
The oak tree behind our house has this big black mark and is oozing brown sticky stuff from it. Is it a viral/bacterial infection and do I need to deal with it to stop it spreading to other trees? Thanks

Certified GKH Gardening Expert
It is, likely, bacterial! Usually, infections such as these are not treatable in older trees. Issues like this will, usually, resolve themselves over time, and will not require human intervention.
Here is an article that will give you some more information on bacterial infections in trees: https://www.gardeningknowhow.com/ornamental/trees/tgen/wetwood-bleeding-trees.htm