Another plant which I'm in the process of having someone eradicate is Chinese lantern. It was growing in our yard when we moved in (over 30 years ago). Since it was almost the only thing growing here on about an acre, we thought that was really great. However, after my Corgi got lost in it for 1 1/2 days, I began to realize what a nuisance it is.
She was on a leash and got stuck in there and couldn't move. Since her previous owner taught her not to bark if she was in a crate, I guess she figured she couldn't bark there, either. I even went to the pound to post a notice since I thought she had got out of the yard somehow. She finally barked, and I called one of my neighbor to see if the people next to her had a dog. When she said they didn't, I asked for their phone number so I could call them and see if they could help me figure out where she was. We stood out there and talked, and they looked from their side, and were going to give up--and then she barked again. The guy finally managed to see her. I went down along one fence where he handed me some clippers to cut my way through. I had to jump and to crawl while he directed me the right way. There she was with her leash tangled so she couldn't move! This was in July, so she must have been really thirsty after that long.
I have a guy hacking on the plant to cut it back, and then he's going to use Round-up. I don't like to use that--never have before--but I don't know of any other way to get rid of it. It spreads by runners and seeds. Some of it is about 10' (maybe more) into a Mexican Elder (Sambucus mexicana). Some of it is growing in the neighbor's yard--but then some of their plants are growing into my yard. It probably got to be 30-50' wide and 20' deep.
The only good thing about it is the hummers like it. But then, I've got lots of other plants they like, anyway. Additional Details
Knotweed - Polygonum multiflorum
Also, Fo Ti or Ho Shou Wu (Polygonum multiflorum) has become a nuisance--plus it's mixed in with Rosa californica--so you can get poked as well as frustrated just trying to clear out enough so the other plants have a chance.
I put in some Vinca which I got from my first herb teacher, John Finch. It's very invasive and probably impossible to eradicate! I was told that Roundup would not hurt Vinca--otherwise, I might even resort to that. Of course, all of these are in with other plants, so it would be hard to get them without hurting the other plants.