What came first:
The depression or the dome?
Answer: Cypress domes form in shallow surficial depressions in the swamp’s underlying caprock, but that doesn’t explain why some depressions capped by a cypress dome and others, right next door, form a tree-free herbaceous marsh.
It might have something to do with the thickness of the marl.
Or maybe fire frequency or flooding depth also factors in.
Mark it down as another mystery of the swamp.