 A conditioner is made up of two grooved rollers which the hay is forced through, causing the stalks to split, thus allowing the liquid trapped behind cell walls (sap and cell sap) to leak out and also giving more surface area for evaporation.The stand-alone conditioner is no longer used on most farms, since the conditioner has been incorporated into mower-conditioners, which combine the mower and conditioner into a single machine.The names Haybine and Discbine are brand names of mower-conditioners, although some farmers use these names somewhat generically.