If that ring of dark material around the soil ball indicates amended planting hole back-fill that was a mistake. If I bought the property tomorrow and was greeted by this specimen sitting newly planted in amended back-fill I would dig it away and re-fill with the same soil that is around the hole, so that the entire area around the tree has the same texture. I would also do something about the difference in grade between the perch the tree is now sitting on and the surrounding bed. And I would let the large area of exposed stems re-grow new side branches, so that the tree again has the even foliage coverage it wants. And I would cut the two columnar arborvitaes down, so that the sphere of influence of the maple is not encroached upon - the two corner sentinels are not an enhancement anyway, even without the specimen tree being right there. That's what I would do.
Hey Ron: It is the same soil built up around oregon that was in the ground. Just put beauty bark around her after building it up to show her off. I agree the two towers should be torn out. One thing at a time. I planted 7 other rare maples in the yard. Thanks for the comments and take it easy. W
That is one of the most impressive Oregon Sunset, probably one of the largest to be found in North America. It was the pride of Del Loucks nusery for decades.