Are the leaves 5–7 LOBED and usually hairy, with 1–1½" long acorns with a cap enclosing 1/3–¾ of their length?
CLUE: This tree is native to California and Oregon.

Are the leaves 7–11 LOBED and smooth; with ¾–1" long acorns enclosed in a shallow cap?
CLUE: This tree is native to eastern U.S.