I think the most common cause of a rapid decline of a recently transplanted tree is not "transplant shock", it is abusive handling by the landscaper. I think that any "exposing of the roots" will likely increase the abusive handling.
Here is a possible scenario, any part of which I think is likely to have occurred:
Then hope. Stick your finger in the dirt before you water it. Damp is good, muddy wet is bad. Here is why: Too much water excludes air and drowns the plant. Some trees like lots of water. Sycamore and bald cypress are good examples. Dogwood isn't on that list of trees that like wet feet.
Here is a possible scenario, any part of which I think is likely to have occurred:
- Nursery has trees for sale. They grow them perhaps from bare root stock, then transplant into "5 gallon" containers. When this occurs, the transplanted tree may have most of the roots cut off so as to fit it into the container.
- Tree might be sold soon after it was transplanted, and long before it is "root bound"
- Tree ape gets assigned to transplant a tree. He digs a hole, grabs the trunk of the tree and pulls it out of the heavy pot. The root ball tears in half, leaving bare roots. Your tree is now in critical condition.
- Tree ape thinks Oops!, and quickly plants the tree as best he can. Customer evaluates, everything looks fine, and they move on.
- Days later, the tree begins to wilt, as all of the fine root hairs recently grown have been ripped off by the rough handling. No amount of watering will fix this problem, either. Customer is told "That's transplant shock, it is common. Your tree should be ok."
Then hope. Stick your finger in the dirt before you water it. Damp is good, muddy wet is bad. Here is why: Too much water excludes air and drowns the plant. Some trees like lots of water. Sycamore and bald cypress are good examples. Dogwood isn't on that list of trees that like wet feet.