Is it possible to make a branch of a Taxonomy tag-able while other parts are not in Drupal 6?

Question

We want to use only one vocabulary to organize the entire site. The vocabulary will have a hierarchy and We're hoping that the terms for a specific branch of the vocabulary tree can be tag-able.

For example, suppose that in our Vocabulary we have a term called "Blog Tags", is it possible to make "Blog Tags" the parent term and have any child term added as tags? Note that blog Tag itself can have siblings that are not tag-able.

Answer 1

Since the 'tags' property is set per vocabulary and not per-term, it doesn't seem that this is possible.

As well, Drupal does not allow 'tags' vocabularies to be hierarchical, though I believe this is more of an interface design issue than an architectural restriction.