Abstract: A hay roll bagging system for bagging a number of hay rolls as have been cut, harvested and dried in a hay field into a plastic sleeve that, is maintained in a stretched state during bagging and then tighten around each hay roll, which sleeve is tied at its ends forming a container. The system is preferably mounted onto a wheeled trailer to be moved into the hay field and includes a cradle structure to receive each hay roll, in turn, and includes a ram for urging a hay roll end off of the craddle and through a collapsing ring. The collapsing ring of the invention is mounted to the trailer across a craddle rear end and is formed to have, in an erected state, a greater diameter than that of a hay roll. The ring receives a folded plastic sleeve therearound when the ring is in a collapsed state.