Location is Portland, OR area.
My new (to me; built 1972) house came with a 10 ft tall Japanese Maple in the front yard. I don't know when the tree was planted but it has suffered through the years from neglect and rather heavy-handed
butchery (ahem) "pruning". The lack of skill is evident even to my inexperienced eye.
The tree is on the North side of the house. During the summer it gets several hours of sun but in the winter only the very top ever sees the sun, and only for an hour or two on sunny days.
I just spent a couple of meditative hours getting familiar with the tree's shape and structure, removing dead wood, and manually picking off a large amount of moss of varying species. I have two concerns (photos after the text).
- Probably over a decade ago, someone hacked off a large main branch close to the trunk, leaving a stump of about 6 inches. It was hidden by the moss, but now that it's visible it's clearly rotting.
- Also hidden under moss in several different areas I found patches of white "stuff". It doesn't come off when rubbed with a gloved hand.
- Should I cut off the stump closer to the trunk to remove as much of the rotting wood as possible? If so, is there anything I need to apply to the new wound that will help the tree recover?
- What is the white on the bark and do I need to treat it?
A couple of overall shots
Two perspectives of the rotting branch stump
You can see some of the white film that was under the moss in these images
Another image of the white film
The white patch on the branch at right was completely covered in the green moss visible on the branch in the middle. Not all of the green moss had white underneath.