I spray brush in the spring with Remedy and Hi-Dep. Always spray patches of thistles with it also. They're right Aaron, if we let them go, even in non-grazed areas, they get worse and worse. May be the difference in winters.
A lot of people 10 years ago put the bugs that eat the rosetts in the thistles. They really worked on the population of thistles. The hard part is you gotta' leave some thistles or you kill all the bugs. Now I only have to spray real problem areas, and let the occasional small patch in pastures grow for the bugs. I'd have to say since the bugs were released our thistle problem has been reduced by 75%. gs