I have a mature larch between my house and garage, in a sort of courtyard about 24' x 24. It slopes toward a cement walkway that connects the buildings. Right now it is bare dirt at the low end and gradually becomes thick grass at the high end of the "courtyard." It is quite shady with the tree there between the buildings.

I am trying to create a flat walking area on what is currently a slight slope. We access our spigot and crawlspace there and it gets a lot of traffic. I also want to be able to leaf-blow the larch needles away for wildfire protection.

1.  I want to lay flagstone down around the edges of the courtyard. Is 5-6' away from the tree trunk far enough?  There is no room to place them any further away. Will the weight or the heat absorption from the stone hurt the tree?

2.  I plan to leave gaps between the flagstones and fill with either river stone or grass (if it will grow). Will filling it with stone just outside the 5-6' perimeter absorb too much heat and harm the tree? Should I just keep it dirt between the flagstones?

3.  The flagstone is 2" thick (or 3" if I use a sand base ) and I would like to raise the ground level directly around the tree to match it, so the whole thing is an even surface and we won't trip. Within the 5-6' perimeter, will it hurt the tree to add 2-3" of topsoil on the low side of the tree? If I do, should I add peat to the soil? Or compost? I could mulch it, but mulch is fuel for fire and also I fear it will blow away with the leaf blower.

4.  Is it a bad idea to dig down 5" at the edge of the 5-6' perimeter to put in edging to separate the area of soil around the tree from the stones?