Maybe Post oak?

I have a HUGE water oak (quercus nigra) in my back yard and the seedlings allways look like those leaves. Even though the parent tree has leaves that are different. I think as they get older the get the 3 lobed leaves.

White oak bark is fairly distinctive so I'd suggest that if the bark looks right then the leaves are just atypical. There can be some variation.

Many thanks to you all! I'm betting esh_ga is correct. I'm familiar with the other oaks and this is a mature tree, so it's probably just variation. I will go back and try to confirm with some acorns later.
You all are the best,
Ging

Looks like Q.alba to me, but oaks are pretty promiscuous, and it could be a hybrid of anything in the white oak group.

Just as with the leaves, bark character can be quite different within a species. Here's a variant of Q.alba that many folks wouldn't recognize...

how young is the tree you got the leaves from ...

and how much shade is it in ...

it takes quite a number of years for a young plant to show its true leaves... especially deep in the understory ... where there isnt the full sun they thrive on ...

ken

Fascinating, lucky_p! I'm so glad you posted that because at a distance I thought the plaques looked 'shaggy', but it turned out that they were just heavily fissured. Now I can see where it would possibly go in that direction.
ken_adrian, don't know exact age of this oak (it's on the property of my new veterinarian's office) but by the trunk size/height/canopy I'm assuming it's in the 50 year range give or take. Probably on the lesser side, but it's a good-size. If I have my directions down and from what's around it I'd also say it gets good strong sunlight for over half the day, but I'm not terribly sure. The Sweetgum next to it is columnar enough not to block too terribly much on that one side and the other side is clear.
Ging

Lucky,

I have never seen a White Oak with flaking bark like that. Lucky you! It looks as if it is very thin; more Birch-like than anything else. Have you ried grafting this tree?

Bob

lucky that reminds me of this big Quercus alba that I saw in 2011 in Georgia.

I often post for oak ID's but the leaves are Q. Alba to me, the bark looks like Shagbark Hickory, but is similar in color to Q. Alba. The Shagbark Hickory "look alikeness" for lack of the proper wording, is of course because of the looseness of that silvery bark in your pic. Q. Alba bark is usually firmly attached to the trunk, my Field guide to eastern trees shows the Shagbark Hickory looking EXACTLY LIKE the bark you've shown, however those leaves are Q. Alba to me. Post oak looks more like a cross in the middle than the pic shows. I guess there is a slight possability it is Q. Lyrata, but MY money, (if I had some extra) is on Q. Alba.

The bark pictures are by other people, not the original poster.

IMO the leaves the are just as likely to be post oak as they are white oak. I have countless understory post oaks that have identical leaves to the ones the OP posted. Bark can be a great help with ID but the acorn in this case will tell the tale. Post oak has tiny round acorns while white oaks have rather large oval acorns several times the size of post oak acorns.

Thanks j0nd03, I'm definitely going to look for those acorns later. I believe you are correct and that will clinch the deal. Sure has been an instructive post, though. :)
Ging

by young.. i meant under 5 foot tall ... as i said.. deep in the understory ...

yours sounds like it part of the tall canopy .... but then i wonder where you got a monkey boy to shimmy up there.. to get you leaves ...

ken

Lol, ken_adrian, 'monkey boy'! Nothing like that, I'm afraid. The tree is part of a landscaped area for lack of a better term. Not in a forest setting. Lots of light all around and I'm suspecting a bit of pruning here and there to keep views/insurance claims under control. The leaves were actually quite low and accessible for my shortness.
I misunderstood, too. I thought you were giving an example of how long it can take for leaves to develop a mature character, not that you assumed this was in that setting. :)
Ging