nehunter-- are you doing anything to eliminate the muskrats?? If you do not eliminate the muskrats, I think any attempt to germinate seed or move plants may not end well. I have a small pond- about 1/4 acre- and about 18 months ago a couple 'rats set up shop in the pond banks. The two soon became five or six. The family made quick work of my aquatic plants- first aggressively consuming and destroying the pondweed, then they proceeded to cut down the canes of the YI. I was shocked at how much damage they were capable of in just one overnight period. I managed to exterminate that "family" after a couple of months. The YI will not recover in the season that the damage occurs. The YI did recover- at least most of the plants- the following spring. Not long after the canes got to about 6" tall, another 'rat showed up late winter '20. I set traps and in about six weeks I had trapped four 'rats total this year (and a mink- probably because the muskrats were present). I was fortunate in that I was watching the pond as the ice began melting and observed the muskrat activity. I got them early before they did much damage to the YI shoots this year.

Just sharing my experience with muskrats and YI so you can be prepared for the continued loss of plants if muskrats continue to be present in your BOW. I had a bumper crop of YI seeds this year. (I recently gave quite a few to another PB member actually, so I can't help you this year...) The quantity of seed pods is directly related to the number of blossoms of course. Maybe the critters injured your YI plants to the point that they didn't bloom very well this year??

Anyway, good luck in your search. As esshup pointed out, the YI are invasive due to the seeds. I have plants that have appeared in the swale area that receives the overflow from our pond. I actually like the plants since they do stabilize the swale banks and slow the water velocity. And then there's the bonus of seeing them bloom in early June.