I am at my daughter's home in Utah at the moment. They have a huge Chinese Elm tree (we think) that has a big, wet area of 'included' bark at a narrow Y where the trunk divides. We noticed it because it is dripping brownish stuff onto the lawn that has killed a patch of grass at the tree's base.
The tree is about 60ft tall and one side leans toward the house. If it fell it would take out the deck and at least a corner of the roof depending on the wind direction.
Getting dark so will post a better pic in the morning. The Y you can see is about 15ft up. Any ideas?