Quoted By:
I grew up on a dairy farm, spent way too much of my life with these.
Its hay that's cut, baled into a large cylinder shape, and wrapped with many layers of plastic wrap.
I see some people here called it "silage". Typically farmers do not call these silage, but more correctly "baleage". Silage is usually stored loose in a silo. It's most often finely chopped up grass, or corn. Its allowed to ferment inside the silo. Baleage ferments inside the wrap. The longer the baleage sits, the wetter, and nastier it gets. It starts to smell pretty rancid after a while. Cows still like it though.
As long as the wrap is air tight, the fermentation is pretty controlled and consistent, so you know how long it will last. Any holes in the wrap and it will get really moldy and ruin the hay inside.
