I have a cherry tree with a three inch (≈ 80 mm) trunk, and I want to
landscape the ground upward around the trunk a couple of feet (≈ 60 cm).

I just learned about Stem Griddling Roots (SGR)
http://www.extension.umn.edu/distrib...es/DD7501.html
videos
http://www.righttreerightplace.com/planting/howTo.asp#

Although this isn't a tree fresh from the nursery, raising the ground
level may give the roots an opportunity for SGR. Are there some
precautions I should take? Should I surround the trunk with something?
If so what could it be? It would have to accommodate the trunk growth
yet prevent the roots from encroaching.

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* Nehmo Sergheyev *
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