Trying to save a very large sweet gum tree
The roots of our very large sweet gum are causing side walk upheaval. The main problem root is 10-12 inches in diameter. There are others branching from that root. Two arborists have given differing solutions. One was to grind the offending root to allow for sidewalk repair. Another was to shave the large root horizontally to level it. What do you suggest?
I am not a certified arborist, and normally I would recommend that you consult with one, but you have already done that (twice). I am not sure which of the two techniques would cause the least harm to the tree, while also ensuring that the roots do not re-grow and cause more sidewalk problems. You might ask each arborist what the pros and cons are. If you are in the City of Portland, you might contact the Urban Forestry department and see if you can have a tree inspector have a look or advise. Especially if the tree is in the right-of-way (planting strip), they may have an opinion. Sorry I can't be of more help.