Imteresting to find you looking Greenhut, as we were doing the same last week!
We usually use debris netting, but this year bought a couple of metres of some sort of plastic backed fibrous stuff (the GC's manager is an old friend, and we all agreed it was quite good kit), and now all I need is some sort of template to cut the stuff!
If I can't find anything, I'll design my own...
It was about £3.50 a m2.