We are landscaping our yard and wanted to extend our deck past and around our large magnolia. I have read that you should not cover the roots of your magnolia with dirt because it kills the roots. Can you put a deck over the roots and around the trunk? LR
Probably, if flooring permits rain to penetrate to the roots, and the hole through which the tree arises is big enough to allow for growth. Do not build your deck flush up against the side of the tree! What kind of supports will you use? Be sure you are careful of roots when placing supports.
The main thing is to not compact or bury the existing root zone. This is generally applicable, and not peculiar to magnolias.