I co-own some property with my siblings, (left to us by our mother,) and one of the co-owners decided to take some shrubs, cobblestones, and flagstones from the property and use them in his own yard. If moral suasion doesn’t work, how else can I can get him to stop?
Good question. Technically, I would assume that you are all co-owners of not just the land, but everything that came with it, including any buildings, plants, etc.
Taking co-owned property for yourself would be conversion (i.e., theft). You might have some trouble getting the police to prosecute, but you could certainly look into a civil suit. Depending on the value of the property and what your goal is, you might be able to do this in small claims court, to keep your costs down.
Keep in mind, however, that it is not unusual for family members to divide up personal property “in kind,” rather than keeping it as jointly owned. You’ll need some evidence that your one sibling understood the intention you all have.