Conditioner (farming)

A conditioner (or hay conditioner) is a farm implement that crimps and crushes newly cut hay to promote faster and more even drying. Drying the hay efficiently is most important for first cutting of the hay crop, which consists of coarse stalks that take a longer period of time to draw out moisture than finer textured hays, such as second and subsequent cuttings.

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.

Mower-conditioners are a staple of large-scale hay making. Mower-conditioners are defined by the mechanisms that accomplish mowing and conditioning.

There are three types of mowers: sickle bar mowers, disc mowers, and drum mowers. Sickle bar mowers use a reciprocating blade to cut the grass and typically use a reel to fold the grass over the knife. Disc mowers have a number of hubs across the cutting width, each hub having a small (18") rotating disc with knives. Drum mowers use two or three large plates (called the drums, about 36" across) which ride over the ground as they are spinning. A sickle bar mower's main advantage over disc mowers and drum mowers is the reduced horsepower requirements. Its disadvantage is the extra maintenance required due to the high number of moving parts and wear items. Disc mowers were historically considered an "all the eggs in one basket" kind of mower because all the mower hubs were in one large gearbox. If one blade hit something and a gear tooth broke, the whole gearbox would suffer a catastrophic failure, and there would be nothing worth fixing. If anything broke, everything broke. Drum mowers prevented this by having typically two belt-driven drums compared to six or more gear-driven hubs. Modern disc mowers use isolated gearboxes, and if one fails it can be swapped out without rebuilding the entire machine.

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