Livestock and crops
The staple foods produced were cereals, grown in all localities in the recently cleared plains and hedgerow country. The main grain crops in Normandy were corn (wheat) and barley, which could also be turned into bread, but was used as well to produce the basic beverage, "cervoise" or barley beer. Stock rearing was common everywhere in fringe areas (on the edge of forests or on moorland) and on land left uncultivated after the harvest, where the right to collective grazing became an established Norman custom. Western Normandy would appear to have gone in for a degree of specialisation in farming cattle in semi-liberty (the texts mention the vaccariae, cowsheds) and horses, needed for transport, tillage and war. Normandy was famous for her cavalry.
The climate was mild enough to allow the growing of vines introduced by the Romans. Regions specialising in this production were the Seine valley, the area east of Caen around Argences and Cesny-aux-Vignes and the Avranches area. Normandy wine was even exported to England, but under the Plantagenets it was surpassed by the wines of the Loire and Aquitaine. Wine was to found everywhere, for it was the noble drink and was needed for liturgical purposes too. There were vineyards in Caen within the enclosure of the village of La Trinité Abbey, and even inside Caen Castle! Cider on the other hand, which appeared during this period, was viewed as a beverage for everyday. Apple-tree grafting techniques had not yet been mastered properly and cider did not become the Normans' usual tipple until the end of the Middle Ages.
Intensive farming reduced the acreage of woodland in favour of tilled land. However the woods could not be done away with altogether, being needed as a training ground for warriors hunting game, and for firewood, building materials, and other timber in a region looking out to sea where shipbuilding was a thriving trade. The forests were therefore governed by a strict system of laws. The needy who had fallen by the wayside of technical progress lived there on the fringe, gathering and poaching, as at Le Neubourg, in the Eure department.
The produce of the sea was another major resource. Salt was extracted from the salt marshes of the Cotentin and around Avranches. Fishing, particularly herring fishing, seems to have been an important activity, and the seafarer's vocabulary preserved many expressions of Anglo-Scandinavian origin. In addition, Normans from the Cotentin to the Pays de Caux went whaling.