Something that I just tried and it works better that burlap and is CHEAP. You've seen that net-like brown stuff cities and landscapers put on top of bare sloaps? It's called Jute. A roll just under 1000 square feet will only cost in the range of 30-40 dollars in the US, and as it's thick and dense, I imagine it will take years for someone like me with about 100 hives to use up. I believe it's make with coconut fiber. Regards to the list Tim Vaughan