Please help indentify this PA tree
I was out in the woods today looking for interesting plants and I stumbled upon this large-leafed tree. There were a few growing around each other, but other than those I hadn't seen them any where else before. They ones only had leaves at the top of the main trunk and at the ends of the branches. The leaves were very large and rounded (6 - 14+ in) and grew right off of the trunk. The trunks were very straight and thin compared to other trees of equal height.
There was a fruit on a nearby branch which was broken off from a recent storm. I'm positive it was from the same type of tree. It was about 3-4 inches, green and reminded me of a pine cone, but instead of hard, woody sections, it had fleshy seed containing "pods". It smelled sweet and a little like pine, but it very well could be unripe and I wouldn't know it. Another thing to note was that the fruit quickly browned after being handled and broken apart.
The biggest trees I saw were only 10 feet tall with minimal branches, so its an undergrowth tree I'm guessing. I managed to find a small tree so I took it home and gave it a temporary home. Any help with identifying this would be awesome.
BTW this is in SW PA if that helps any.
Fruit - http://imgur.com/0hHpP.jpg
Fruit w/ seeds - http://imgur.com/hSs9R.jpg
Interior of Fruit - http://imgur.com/k1rXU.jpg