I've got an area around a tree that has refused to allow the grass to
grow. Today I noticed the area was very moist so I decided to take a
rake and turn the soil so I could try again with some seeding.

I found a tarp on the area underneath the dead sod. The guy that
installed the sod a year and a half ago told me he found a tarp and
had given me the impression he would remove it prior to putting the
sod on top of it. Obviously he has misled me.

Any ideas on why the former homeowner would put a tarp down over the
tree roots and stuff? Makes no sense to me. The tarp covers about 25
square yards.

Thanks for any ideas you might help with.