In Kansas we have noxious weed laws, probably a dozen weeds have been declared "noxious", meaning that if you don't control them the county may do it for you,and charge the costs to your taxes. The newest noxious weed and without a doubt the most expensive and difficult to control here in the Flinthills is sericea lespedeza. This weed was introduced in this country for wildlife habitat. It was only after the government had spread it far and wide that it was discovered you couldn't kill the stuff, and cattle hate it, and must be starved to eat it, although goats love it and sheep will eat it, problem is there are precious few of those in Kansas. Fire, our chief tool to keep our pastures clean and weed free only makes it grow bigger.
I have been battling this weed about 15 years and making very little progress. Tomorrow I take the battle to a new level, aerial attack. I am going to bite the bullet and have 160 acres sprayed from the air. The sad part of this is that I already know next year I will still have it. Hopefully this method of spraying(the terrain is too rough to spray with a ground rig) will at least help me get an edge so we can do some mopping up next year on foot, but I wouldn't be a bit surprised if I have to call in air strikes next year and the year after.
The bad thing about sericea is the cost of controlling it is sometimes more per acre than the grassland will make. It pits neighbor against neighbor because hard feelings ensue if one person feels their neighbor isn't doing enough to control it. Each of our counties has a noxious weed department, and most counties now subsidize the chemicals used to fight this battle, and that has helped bring costs more in line with what farmers can afford, leading to my decision to blanket spray.
A word of advice....don't ever plant sericea no matter how good your government tells you it is.