I don't know what it is but the leaves have bristles so in my opinion not in the white oak clan.

Water oak is an oak in the red group that stays green very late, but the leaves aren’t right.

It may be a Q. buckleyii (texas species).

Some oaks are very stubborn and refuse to defoliate until a very hard freeze (below 20).

I have been as cold as 17 here in Howard County this month, but most of DC proper probably hasn’t gotten below maybe 25 or so.

Could also be a far southern provenance of Nuttall Oak.

Agree w/hair that it may be some or all Nuttall. My Shumard x Nuttall holds its green leaves pretty late, later than pure Shumard (also new leaves emerge early).

interesting! did not know there were such oaks in the area anywhere but botanical gardens. I knew some red oaks tended to color late, but not this late. Maybe the strange weather we had this year is a factor, too. My fall colors were pretty bad.

I will keep an eye on it if I'm in that part of DC again.

It does make me wonder...if these oaks‘ leaves are that tolerant of freezing, why bother even going deciduous at all?

hair, IIRC, I read oaks were warm-climate trees that moved into temperate areas & have only recently "developed" deciduousness -- some only somewhat & others not at all.

Ridding of leaves in the fall lessens chances of snow and ice weighing down branches and breaking them. You may see semi evergreen oaks loosing most branches after blizzards in places where they don’t usually have snow.