In the late Anglo‐Saxon and Norman periods an oxgang was a conventional unit based on the amount of land that a team of eight oxen could plough in a year. It is clear at this time that the ox, rather than the horse, was the animal that was used to draw the plough. In many regions oxen remained the choice for ploughing long after men started to prefer the horse for haulage and harrowing. The change to the quicker, more agile horse for both haulage and working the land was an extended process lasting from the Middle Ages to the 20th century. The arguments that were advanced in support of one or the other animal remained the same over the centuries. Oxen were admittedly slower and more cumbersome than horses, but they were stronger and had more stamina. Moreover, they were easier and cheaper to keep, less liable to succumb to disease, and they could be fattened and sold as meat at the end of their working lives (see Durham Ox). On the other hand, they could not be used for riding. Horses were suitable for light soils, but oxen were preferred on stiff, heavy clays. The pace of change therefore varied considerably from one agricultural region to another. Regional preferences in the early modern period, which saw considerable movement away from the horse, are best revealed by a study of probate inventories. See John Langdon, Horses, Oxen and Technological Innovation: The Use of Draught Animals in English Farming from 1066 to 1500 (1986).