a bag support for a riding lawn mower grass collector includes a rectangular framework attached to a mower with grass directing hood . a grass bag has a resilient frame extending substantially around bag opening . a much larger leaf bag has a resilient frame extending substantially around bag opening . frames include three continuous coplanar sides and a fourth side with a central open space bounded by a pair of handles extending perpendicularly outward from frame . the sections of the fourth side adjacent open space are at an acute angle to the plane of the three coplanar sides . frames are configured to match separate portions of framework . framework includes transverse brackets and at locations to correspond with alternate sizes of bag or . handle retaining brackets are attached to rear of framework to receive handles . brackets , resilient frame , bracket or and angled segments of the fourth side of frames cooperate to provide a sealing engagement between framework and matching frames . framework can thus support a plurality of small bags or a single larger bag by utilizing brackets or , respectively .