Yes I have some as well at the farm. For some reason it is just between or cattle fence and the road. Maybe the cattle flatten it out before it gets a good start in the pasture. I have tried round-up on it but it appeared to have no effect. An excavator digging it up over a couple of years is probably the best.
If it's running bamboo, its a nightmare to kill. We have it at home and its horrible to kill. You can't just rip it out as it has runners under the ground. If you don't get them all, they will pop up again....
I think you guys are right, Japanese knotweed. Someplace I found that what ever is in roundup can be effective in combination with constantly cutting but you have to be dilligent, constantly treating it, almost as if you are wearing it down trying to overcom the herbicide.
Maybe try some 2/4D
Good luck with that, had a neighbor one time who like how it looked... Needless to say, before you know it it's right on the property line. I cut my side and leave his be... Maybe it'll all burn one day, probably just be back the next day.
Tortan stump killer works good on brush it will go through the roots. Dicamba is another good chemical for brushy weeds. Problem with round up is there is no residual so it only kills what it is absorbed into. When spraying hard to kill things some Dawn dish soap or crop oil helps it stick so it doesn't run off as fast
