What do you call one or more trees with disjointed namespaces?

One or more trees with disjointed namespaces are commonly referred to as "namespace trees" or "disjoint namespaces." In computing and data structures, this concept is often used to organize and manage data in a way that ensures that identifiers in one namespace do not conflict with those in another. Each tree can represent a different scope or context, allowing for clearer data management and organization.