We do have a lot of clay here. When I planted it however I excavated 2x the pot diameter X 1.5x pot height as instructed. I then mixed in bought potting soil with the soil from the pot and added some bone meal. So there is no clay soil near the plant
A guiding principle in the nursery/landscaping business:
if one has predominately clay soil
DO NOT dig a deep hole and fill it with potting soil or other richly organic mixture

; by so doing one is effectively creating a
bathtub filled with a sponge which will remain filled with water because the surrounding clay soil will not quickly absorb much of the water.
It appears that this maple tree is being drowned with excess water and very little air entering or remaining in the soil.
In clay soil it is best to till/mix the top two inches of clay with other added soils and amendments to raise the planting area (generous area) and plant into this raised berm. The plant will have adequate air and moisture and be able to access the characteristicly retained moisture of the clay soil below when the roots grow and mature.
If one has predominately
sandy soil then by all means add plenty of the potting mixture or other organic amendments to help retain moisture. The surrounding, well-drained sandy soil will wick away excess moisture for a more healthful environment:thumbsup:.
If this tree was mine I would dig it up and replant as described above and I believe the tree will have a better chance of surviving unless it has already passed the point of recovery-- hope not!
More plants are lost from excessive water given with thoughts of TLC than any other factor.
:2cents:
HTH
Arkaybee