I agree. Looks like an oak seedling.

Yes, oak. Probably has an extensive root system and long tap root already.

Thanks or the comments all.......going to leave it, its in a place where it shouldn't be a problem, at least not for a long time. Lot of older dying trees here so we can use this one if it survives.

i walked around a bit today and found 3 more. I guess the squirrels aren't getting all the acorns!

They never do. It's nature's way. ;-)

" I guess the squirrels aren't getting all the acorns! "

Well, likely it was the squirrels that planted the acorn.

If you're keeping it in it's current location, I suggest placing cardboard around it and placing mulch atop the cardboard to kill the grass. Mulch should not touch the seedling. A wire cage will protect the seedling from humans, animals and errant soccer balls.

Yes, squirrels plant the acorns to store them for a food supply during winter and spring.

And they never get them all. It might be poor memory or maybe they just stored more than they needed. Could be a hawk gets the squirrel so there's no more squirrel to eat acorns.

What cecily said.

Seedlings and saplings don't like to compete with grass and other surrounding roots.

Putting carboard around the tree and up near to the trunk with an inch or two of wood mulch on top is a 'One and done' method to eliminate grass competition.

The mulch also provides nutrients to the trees as it decomposes.

Then it's a simple process to use chicken wire and a couple of garden stakes to surround the trees.

Shown below is 2ft. high chicken wire but on a deciduous tree, 4 ft high wire might be better bc it will keep deer from reaching over the wire and snacking on the top of the trees.

I plant all my new trees this way but take care of the grass beforehand.