My wife has a collection of bracelets and charms from KEEP Collective and her desk was becoming a huge mess, err collection of charms.
I showed her that 3D printing isn't just for geeks. After 3 iterations we landed on this design that's simple and effective. You should end up with a snug fit between the tree trunk and the base. If necessary you can use superglue; I didn't need to.
**Update: 2018-01-18:** I've posted a modular jewelry stand that's an overall improvement on this design in terms of capacity and configurability.
The author hasn't provided the model origin yet.