I wish there was a way that I could attach a slave owner's name or family to a particular person, not to include in the tree itself, but some sort of link that I can reference.
I have found information about my own ancestors (Black) from tracing white slave holding families. For example, I was able to find a freedman's bureau record with the names of my ancestors, because the white slave holder's full name was in the record (although only my own ancestors first names were included). I have also found the plantation and white slaveholders where I got my last name from (Long). Also, I have found the name of one of my slave ancestors in a will record (not on ancestry) when my cousin did research at a courthouse.
Slaveholders often died and left slaves to their family or sold them to other family members or gifted them in marriage etc. When slaveholders moves, their slaves sometimes moved with them. Sometimes when you trace a slave holding family you can see who their sons and daughters were, who died and when and determine if there are any will or church records that might be helpful to your search.
Right now I just sort of jot down who I think could have been a slave holder in a separate space along with their family members. It seems like there is some way that that sort of thing could be integrated in to Ancestry's software program.