We have a small grove of Cedars (quite large...perhaps 80' tall) that has perfect space underneath them for a small shed. We're looking at putting a small one (less than 10x10') underneath them.
Would this in any way hurt the cedars? It's well within the drip edge, so it's usually pretty dry under them so assume that this wouldn't hinder water intake for the trees, and the root diameter (if it matches the branches) is at least 25' so the shed footprint would be fairly small in comparison.
I'd plan on using a loose rock foundation or, if preferable, some concrete post blocks.
BUT...we certainly don't want to put the health of the trees at risk, either.