What is the soil like any ways
Me clayish ( no sand)
I think I might try to take a pick ax, and pore sand/gravel down ,
and pick ax it into the soil by my tree.
I've thought that since I got the tree , but seen them in other thick soils
but reading about the melting of lake Michigan glacier ,
and my soil type (and surrounding )
in a new (native) plant book I got is motivating me more into it.
Kankakee IL. soil is better for them it mentions.)
Some times I wonder if the seed or genetics of the root stock could be affecting certain trees differently , but not sure of the seed source from your tree
Like what if the parents grew in extremely airy soil, but now they are in moderately airy soil.
I cannot say for a older tree, but I saw saplings extremely root rotten
the root bark was coming off placed in extreme shade for months , and they started re growing (I mean it was amazing They did die of neglect of me tough over winter.)