On 7 Jul, 12:49, "David \(Normandy\)"
wrote:
Just had a closer look and they all seem to have vacated the premises!
They were definitely the mullen moth caterpillars though - I googled them as
suggested and they look exactly as I remember them. Another small (first
year) one was growing in the veg plot a few weeks ago and it was absolutely
writhing with them. As it was next to lots of veggies I pulled it up and put
it in the compost. In retrospect I could perhaps have left it if the
caterpillars are specialised feeders of that plant alone. I'll know next
time and just leave them to it.

Just vigorously rake the whole thing ... it's 'orrible. You can borrow
my father in law for the job ;o)