Soy bean seed crate bags from seed dealers and silage pile plastic from farmers. A lot of seed dealers around here are going automated, so my seed dealer friend brought me a dozen of them, one will last for years for most, the silage plastic will last for many years. They are about 4x4 square and weigh less than 60 pounds. Sorry, no pics, my computor is ailing and I don't have photobucket at the moment. Here's one. You bring me three of those excelcior bails and I will give you three seed crate bags.