Question
We seem to be having difficulty keeping a Japanese Maple tree alive in a particular area in our yard.  We have lost two trees now and the last tree I removed showed signs of root rot and the root system was very soggy wet.  I also noted that water was seeping from the side of the walls of the hole I dug to remove the tree.  It appeared to have a lot of red clay in and around the hole dug to remove the tree.  In fact, I had left the hole for a few days without filling back in and after a subsequent rainstorm the hole was standing in water.  
It seems that the clay is holding the rain and any water from my sprinkler system and this is ultimately killing the tree due to rotting of the root system.  Do you think by digging a large enough hole and filling with a quality top soil, peat moss, etc...that this would be sufficient?  I do not know how deep the layer of clay may be.  Otherwise, I suppose I could keep digging the hole through and removing the layer of clay.

Any thoughts or suggestions will be appreciated.  Thanks.  

Answer
Hi Bruce, In an area that's moist, the worst thing you could do would be to remove the existing soil.  You would create a clay bowl that would hold even more water.  The only way to grow a plant that doesn't like a lot of water in an area that has a lot of water is to elevate the rootball above your soil line.  
As wet as it sounds, I wouldn't dig at all.  Set the rootball on top of the ground and bring in a soil mix that is at least 70% clay, combined with finely ground pine bark.  Create a mound that is 6'-8' wide so it appears planted on a little hill.
You'll need the clay in the mix to keep it from drying too quickly in the summer and for winter protection.
You could build a fieldstone wall around the mound for an attractive elevated planter.  Add a few hosta or some seasonal color and you've got a nice planter and a happy maple.  Jim