Cinnabar moth caterpillar on garden grass

I was asked to move our car  by the neighbours this afternoon, as they needed space to manoeuvre their horse box. As I walked out to the car on the road, I saw this caterpillar on a long leaf of a grass. So once I'd moved the car I went to get my camera.

I had to lie down on the stony ground which was a bit uncomfortable and then found  that it was surprisingly breezy. The grass just wouldn't keep still, so it was tricky to get good focus.

I didn't recognise this type of caterpillar, but having checked online I'm pretty sure that it will become a cinnabar moth (Tyria jacobaeae), which I read is a brightly coloured arctiid moth found in Europe and western and central Asia. Apparently it flies during the day and is easily spotted because of its bright red and black colouration.

'These bold colours and patterns warn birds and other predators that this species is extremely unpleasant to eat. Cinnabar moths can be found throughout Britain, except northern Scotland, wherever its larval foodplant, ragwort and groundsel, are present. The adults drink nectar, but the caterpillars eat ragwort and groundsel.'

This is interesting to me as I feared that a yellow plant which is now growing a bit too freely around our house and in the garden is ragwort.

'Ragwort (Senecio jacobaea) is not usually a significant problem in gardens, but its poisonous qualities can make it a serious weed of paddocks and gardens backing onto fields grazed by horses or cattle.'

We have cattle roaming the hillsides and pasture behind our garden and the neighbour has horses which occasionally are brought here in their horse boxes from their stables up the valley. I think I'll try to remove the ragwort from now on whenever I find it, although that might mean we lose this moth. But we do have an abundance of other moths, although mostly they fly at night and appear in the house through open windows.