Which TREE species is most likely to cause clay sub soil problems?

Question

Which tree species is most likely to cause clay sub soil problems?

Larch, Elm, Ash, Oak, Plane, Horse chestnut

Answer 1

It's not the tree that causes the problem it's the clay that causes the tree problems.
It's unable to have a good root growth because of the poor drainage and the compaction of the clay. It's can actually cause a young tree to die. Too often the sub soil IS clay. You might want to read the link for more information.

Tree Problems
Excerpt:
In areas where the subsoil is a heavy clay, a recently transplanted tree may die, because of excessive water in the soil. Filling the planting hole with good sandy loam or peat does not change the water problem.
http://www.wvu.edu/~agexten/hortcult/treeshru/treeprob.htm

Answer 2

Trees do not cause a clay situation to develop in the soil.