The conservation areas in Lexington, MA have a lot of invasives, including the despised Japanese Knotweed. We also have two expanding stands of pawpaw and nothing seems to grow where they have taken hold. I have always wondered who would win in a territorial war between knotweed and pawpaws. The pawpaws are naturalized, native to the mid-Atlantic, but not here. These two species are growing pretty close to each other in one area but not overlapping. Would it be interesting to study (e.g., by marking the boundaries of the current stand of knotweed) to see over a period of time who is winning? I have also wondered whether we should try growing pawpaws in conservation areas that have been largely invaded with shrub honeysuckles, false buckthorn, etc.
I think that would definitely be interesting, if only for curiosity’s sake.
However, even if the pawpaws win, I’m not sure planting them in areas where they aren’t quite native and do agressively well would be a good idea. It might end up out of the frying pan into the fire.
Pawpaws are native here and I have not seen them crowd anything else out - native and non-native shrubs alike grow right under the pawpaws. I like them because they create a nice “middle story” between the tree canopy and low shrubs like spicebush.