"The mysterious large pile is silage..."
Oh, I shouldn't have changed my first thought! 🙀 Many farmers around here roll hay into giant, cylindrical bales. If they're not transported to a barn or other shelter, they're covered — but, in a different way! So, I changed my answer to 'mulch' instead! 😂
Don't feel bad; no one guessed, but you have to admit, there were all kinds of possibilities! Thanks for participating and have a lovely day!🤗💜