Pickers roll and depending on the equipment, there are a couple of different things that happen. As Alicia mentioned the other day, there is equipment called a boll buggy that may be involved, or a module builder or the picker can have an on-board moduling system.
Cotton used to be put into wagons. Someone would get in the wagon/trailer and jump up and down to compress it. The trailers would be taken to the gin and once emptied, it could be refilled. Farmers had multiple trailers but almost nobody could afford enough to keep harvesting non-stop.
Moduling was probably invented because it answered a problem farmers had. With a module builder, the cotton be placed in there. The machine would compact it thoroughly and a tarp could cover it until it was transferred to the gin. This kept more cotton from having to take rain directly, etc.
Because everyone loves a big piece of machinery, I thought I’d post video I shot recently at my friend Bob’s. This is an on-board moduling picker from Case IH. I wasn’t ready for the picker to dump so I ended up shooting it from the car. It’s still sort of cool though (despite the mirror showing up some LOL)!