Hi Greg - I came across your post when looking for how to contact you at your new position. Thanks so much for sharing these thoughts here and I hope to see others respond - this is definitely a topic that needs to be discussed and explored as we are now several years into large investments in invasive species removal and can step back and see what is working on longer time scales. Where it is not working in a more sustained way (i.e. without constant removal or management efforts), we need to ask the tough question of what could we do differently to facilitate the system to move in the desired direction. Obviously these are complex systems with so much more to understand than simply the characteristics of the invasive species themselves (see, for example, news on microbial associations of invasive and native Phragmites: https://www.sciencedaily.com/releases/2017/09/170905145600.htm).
Other researchers are also noting how changed systems - e.g. hydrology, nutrients - may be the real issue to deal with vs. the invasive species themselves, as removal will only lead to return of that invasive or another that is also adapted to those altered conditions. Of course, systems are more difficult to manage than species presence/absence (reducing upstream nutrient loading vs. herbiciding Phragmites), but if we do not take this broader approach it seems that all of of our efforts may not, in the long-term, actually benefit the areas we aim to restore.
Interested to hear others thoughts on this.