If there's regrowth you've done it wrong! Best keep an eye out for very early creeper shoots and let them get a bit of a start.Find thistlex better than grazon, spray at a rate of one litre/ha in 200-400 litres of water. it may pay to spray re-growth two to three weeks later.
I suppose being an arable man you wouldn't think of it as an expensive spray? The trick with them is to get them in one go and thistlex is capable of that. I think the trouble starts if the creeping thistles have sent out their spronkers that haven't got enough leaf to get enough chemical. If they're real thick with small underneath I guess it'd be better to top and come again as much as I hate the idea of a topper.Just the way ive done it in thick area's
they are great little finches, ive seen these little fellows after dock seeds in my garden!
and I am sure sheep with the same regime will do the same to the docksWe had a farm walk somewhere that had been rotationally grazing cattle for the last 7 years, latterly with big mobs on daily moves. His thistles had all disappeared, apart from the fields he grazed with sheep, but docks were having a barmy time of it.
The general consensus was that cattle, with enough grazing pressure, were grazing the thistles out tightly & regularly, and consequently killing them.