jack oak

(noun) a common scrubby deciduous tree of central and southeastern United States having dark bark and broad three-lobed (club-shaped) leaves; tends to form dense thickets. Synonyms: blackjack oak, blackjack, jack oak, Quercus marilandica.

(noun) small to medium deciduous oak of east central North America; leaves have sharply pointed lobes. Synonyms: jack oak, northern pin oak, Quercus ellipsoidalis.