Plough teams, together with mills, were the two major sources of power in the early medieval economy. Domesday Book shows that England was rich in both.
As with mills, we would have no conception of the extent to which this power was utilised in the early medieval economy but for Domesday Book. Domesday records well over 80,000 plough teams. Since the standard Domesday plough team was a large one, drawn by eight oxen, this represents about 650,000 oxen.
These figures, however, make no allowance for the losses resulting from the Conquest. In circuit 3, for instance, a deficit of over 16% is recorded. In the words of the texts, 'there could be' over a thousand ploughs teams more than were actually there. Circuit 3 was far from being one of the most vulnerable parts of the kingdom so it is reasonable to extrapolate this deficit to the country as a whole. On that basis, making some additional allowance for Yorkshire and other areas wasted by the 'harrying of the north', there would normally have been over 100,000 plough teams, or 800,000 oxen. On average, therefore, every Domesday vill was equipped with 7 plough teams. It has been calculated that there was as much land under the plough in 1086 as in 1914. In early medieval England, 'the plough was king' and the country was rich in animal power.
For plough teams, see H.C. Darby, Domesday England (1977); and John Langdon, Horses, oxen and technological innovation: the use of draught animals in English farming from 1066 to 1500 (1986).