Tell us about yourself!
I also had this exact idea to reuse the feed sacks to do the same thing to cover a very large number of round bales, 90-100. In the depression the farmers used feed sack material to make clothes an quilts so I was thinking along those lines. Two layers of the feed sacks with a layer of i dunno maybe bubble wrap in between and then sewn together and sewn in a grid to lock the layers. If you could have aluminum window screen mesh as the core sandwiched with bubble wrap then the feed sacks, wow talk about indestructible farm quilt tarp. You could roll it up like the tarp covering baseball diamonds an even drag it around using a tractor up an on top of the years hay crop then steak it down with rebar like a circus tent. :-)