Here is it just before re-planting it in a pot.

Red oaks are very difficult to define at that age/size.

it takes a few years.. for a babe of a tree .. to perfect its mature leaf form ...

i am surprised the nut is not ID'able ....

perhaps one of the tree nuts in the tree forum will recognize it ..

ken

admirable thing to do- sometimes I wish I could do what you're doing for this seedling.

If you can find the parent plant, we might be able to ID it better. Be sure to grab a few leaves to show the range of leaf shapes if you can.

Here is a close up of the parent tree. I'll post another shot of it from farther out. The tree's branches are far up so I'll try to get a picture of a leaf that has fallen. Not to mention, people were looking at me crazy while I was taking pictures of the tree!
@surya55 I couldn't leave this little guy where it was. I knew it was only a matter of time before it got mowed over or trampled, most likely both! It was also 9-11-13 so I was feeling even more sympathetic than usual. Our little tree is named Patriot! :o) I also like to rescue succulents that have broken off at stores and are on the ground. They usually root very easily and I get a free plant. The store people, so far, don't mind.