Quercus x rudkinii is a tree in the red oak group.
Leaves very variable, even on the same twig; stalk very short, top blunt with bristle tip; base rounded to slightly lobed; margin entire or with blunt lobes; young leaves hairy, often rusty coloured below.
Flowers monoecious, small, males in catkins, females 1-few together.
Wetland status: NL.
Frequency in NYC: Rare but unlisted.
Habitat: Not fussy.