Yep, looks like the lucky charm. Yours are just elongated.

Bur oak.

There are so many subspecies, I don't put much stock in oaks leaves. I go by what they produce and the bark.

My part of East Texas....we would say that is 'Bastard Oak'.

Loves to sprout where the soil has been disturbed. Most often grows to not much more than a shrub or small tree.

I know one thing, I could never identify trees for a living. I would pull my hair out (if I had any).

Thanks, flintnapper, for throwing that wrench in, lol. Looks like another one I'll have to research. As fast as these things have grown, I'm thinking they're probably not going to be a bush. But, I could be wrong!

I was reading about the bur and seems deer don't always like it. Getting the nut free from the shell can be a chore. The nut is huge and deer may not want to swallow it and may have a hard time digesting it. But the quality of nut and taste can be dependent on geographic location, soil type, and even varies from tree to tree even if all other conditions are the same. I am needing a good producing white oak. Of course by the time it grows enough to start producing, I might not be around any longer!

Those acorns look too small to be Bur Oak acorns.

As for leaves (pointy lobes or rounded), I’m with Texas Buckeye. Pointy - red oak family. Rounded - white oak family. As for Live Oaks, there many opinions as to whether they are part of the Red Oak Family or the White Oak family.

And you could taste the acorn. Red Oak is way more bitter than White Oak acorns.

What does the underside of the lieaf look like, kind of almost hairy or white-ish looking?

I'll be out there in a bit. I'll take a pic of one.

So I see tiny little bristles on the lobes, not a white oak perhaps. Post oak has white-ish almost hairy underside, supposedly.

Too many lobes to be a post oak, I believe.

The sinuses aren't cut as deep as I previously thought and got me to looking closely at the bastard oak. But the bastard oak lackes the amount of lobes. That's my determination of looking through many pics, anyway.

It would be nice to have a arborist on here to finally put this to rest, lol.

I could key it out with twigs and acorns and leaves but need them in hand.
Page 120 starts this key: https://www.fs.usda.gov/foresthealth/technology/pdfs/fieldguide.pdf

That's a great link, thanks. I'll refer back to that as time goes on.

Unfortunately, they are still seedlings so leaves are the only examples I have at the current time. I have taken one sucker plant off and have planted it separately. I left the rest on the main root system to grow on their own. Maybe one will start to outgrow the others and I'll remove the shorter ones and let the fastest growing one continue to grow.

The trouble with trying to identify with ONLY leafs (at such a young age of the plant/tree) is that they may not be 'representative'. You will note quite a bit of variance between leaves.

A good example being Water Oak leaves. The leaves at the bottom of the tree often looking very different from those at the top.

As suggested by someone above, you would need to 'key' it out (examine leaf structure, texture, features, look at stem 'pith', acorn, bark, etc) and that simply isn't possible with the specimens you have at this point.

If you don't have any mature trees around/near then clearly these are NOT 'suckers' growing from the root system.

Likewise, if sprouting from acorns found locally....then we could expect to see evidence of that.

OR....it is not a species that normally grows into a large tree (like Bastard Oak, Shin Oak, Scrub Oak) in different parts of the State.

We have tons of Bastard Oak where I live (Deep East Texas) and it is a nuisance in most cases...requiring frequent clearing along with other species.

Hope you find out what it is, but it would probably take a dendrologist to positively I.D. it from a leaf only.

flintknapper, the only trees closest to them are water oaks. No other trees are around that area as we've had the area cleared. They are most definitely on a root system, though. You can see where the plants are attached down the root line.

But I agree that there has to be a tree around keeping them alive. I just don't know where it's at. Wherever it is at, it is a vast, far reaching root system.

Oh, something just came to me. Before we had our place cleared, I had hand cut some smaller trees with the chainsaw. That's where it's probably coming from. The guy that cleared our place never dug them out since they weren't in view.

Like flintknapper said, leaves on seedlings/saplings oaks can vary greatly and make it difficult to identify. Habitat will play a big role, such as soil type (sand, loam, clay, etc.) and drainage (hilltop, side slope, etc.). Just by the leaf, cherry bark oak could also be an option. Pretty common in E. Texas, but at that small of a tree that is also a guess.