mounting above the graft on established trees?

We have a few well established peach and apples trees. They were grafted on to hardier root stock for our climate. Recently my wife and I mounted shaving mixed with horse menu re at their base and planted irises and garlic. The mound is higher than the graft mark.

My understanding is when planting it isn't a good idea to have dirt above the graft mark because the scion will root.

Is it OK to have mounded compost/manure above the graft line if the tree is well established or do we need to change it?

The only reason you would not want the scion to root is because it will eliminate the dwarfing influences of a rootstock. If you are not worried about a dwarf rootstock then it is better to let the scion root. You will have a much stronger tree in the long run.

I would pull it back for a different reason. Manure and shavings are going to make a fine rodent habitat for bark-gnawing little beasties.

Thanks Akira Silver. In this instance our peach tree in question is pretty large (maybe 12 feet tall and 5 inches at the trunk). I think it's past dwarf but don't know for sure.