Are there any common trees that produce berries that look like mulberries, but are poisonous? My neighbor has a tree that I think is a mulberry tree, but I don't want to start plucking berries and munching them if it might land me in the hospital. How can I tell for sure if it's a mulberry tree, or some other sort of tree? The neighbor has no idea what it is, by the way, and would be perfectly happy to have me picking some and keeping those messy black berries from staining his sidewalk. Thanks!