leaves will confirm it, if you don't want to take my word for it. They have a very unique "trident vein" in an otherwise plain leaf leathery leaf. They tend to get galls on the twigs which is how I identify them from far away. And the leaves almost always develop little galls on the under side, forget what they're called but they are inhabited by some kind of harmless bug.
*edit, this could have been one post. apologies, I kept thinking of things to say....