Guardian of our countryside in action

The roadside verges here are lovely at the moment (except where NYCC Highways dept have mown them flat). However, this farmer didn't like the one opposite my house much.

He's spraying using Thistlex which does for the dicots as far as I can see - three days after spraying the Cow parsley is looking very unwell. His excuse was he wants to keep thistles and nettles out of his fields. I can't understand why he won't just spray his side of the wall. The national park don't seem very interested in this activity, I have had a reply to my email but it isn't very wildlife friendly. I was rather hoping they might have quite a strong position on this kind of environmental destruction.

Anyone out there seen much evidence of farmers behaving like this? - I can't recall when I last saw a farmer do this and have seen little evidence of it elsewhere locally.