Wisteria macrostachya (Kentucky Wisteria)..... Agressive or Not?
While in Virginia, I was aware of Wisteria floribunda (japanese wisteria) taking over wild areas and smothering other plants indigenous to the area. Does Wisteria macrostachya have the same tenancies? I would love to use it on the farm but not at the potential expense of natural surrounding areas.
According to the following source from the University of Illinois, it does not.
http://extension.illinois.edu/vines/perennials.cfm -> less aggressive than some of the others.
The below U of M source discusses wisteria hardy to zone 3, including how it should be pruned to increase bloom. If you prune it as advised and also remove the seed pods, it should be fine. The reference does not mention what might happen if you just let it fly because most gardeners don't have that as a goal. You probably don't either.
Bottom line: Give it something strong to grow on in a sunny location and train it to grow there. Prune it for more bloom. If an errant sprout suddenly appears amid your peonies, cut it off at its source. Now that we finally have some cultivars that are hardy here, we are fortunate in that they do not behave as badly as those you saw in Virginia.