What is "jack oak"

n. a common scrubby deciduous tree of central and southeastern United States having dark bark and broad 3-lobed (club-shaped) leaves; tends to form dense thickets [syn: blackjack oak, blackjack, Quercus marilandica]

small to medium deciduous oak of east central North America; leaves have sharply pointed lobes [syn: northern pin oak, Quercus ellipsoidalis]