Is there ANY way to get rid of horsetail reed?

Good luck OP. Kill it with fire.

The best suggestion is to cut it often. This will slow it down and eventually it will die off. For me this is impractical as i have 200' of ditch with this shite growing in it along a busy highway. It's been a seven year battle so far.

This plant has a very high silica content. So i figured is try muratic acid strong enough to burn concrete. It turns it black and knocks it back, but doesn't quite kill it. The acid neutralizes fairly quickly and therefore isn't as bad as diesel and i haven't seen any negative downstream affects.

I've also tried various mixtures of Amine400, glyphosate, and a surfactant with about the same effectiveness as the acid.

I tried about 80 lbs of salt on one of the ditch just to see, but i think rock salt wasn't the best option as it doesn't dissolve fast enough. Maybe a faster dissolving salt will work.