Hey Juniper, I forgot to tell you I typically just fold and double layer the tarp and put some large cuts on top or with some thin cut cinder blocks. I cover maybe .5 or 1 foot on the sides. The previous owner had the thin cinder block plates laying around that are heavy and ideal for weighing down the tarp. It doesn't go anywhere. Patio stones I think they call them. Like this They are cheap.
I do pallets and have pallets in between and on the ends...I am most fortunate to have a bunch of 8 ft. metal roofing and I screw it to the pallets. I can store my winters wood in my garage so not a problem but if you have to use from the outside stacks just put some grade stakes upright to hold everything up when you are emptying them with snow on top....Works slick...
milleo I use these for my ends: and pound them through cinder blocks like this and put planks across the them. That way all wood is off the ground and I can easily move them whenever I want to.