Mulberry for sure. Mulberry trees come in male or female. When people buy fruitless mulberries, they are buying trees that are grafted males. The only way I know now to tell the difference is to wait till spring and look at the blooms. The female blooms look like tiny bulberries, and the male blooms look like little fuzzies with no berry at the center. Some mulberry trees have two shapes of leaves on one tree. I don't remember whether that is the female type or whether it can occur on either sex.
WA