What's the scoop on hay tarps?

Next year I plan on doubling my straw production from 5 thousand bales to 10. My current straw barn will hold 5,500 when its jammed full. I have a nice stone lot next to that building that I'm strongly considering stacking the remainder of the straw and tapping it. Also I live in central Ohio. It rains and snows alot here. Hahaha what are some experiences that you guys have had with them. What are some good brands of hay tarps and ways to fasten them down. Also do you lay a trap on the ground and wrap it up or stack on pallets?

What's the scoop on hay tarps?