There were several thousand thegns, rich and poor, who held land directly of the King. Some thegns had soken or jurisdiction over their own lands and others did not. Free farmers who had sought protection from thegns in time of war now took them as their lords. A freeman could chose his lord, following him in war and working his land in peace. All able-bodied freemen were liable to military service in the fyrd [national militia], but not in a lord's private wars. In return, the lord would protect him against encroaching neighbors, back him in the courts of law, and feed him in times of famine. But often, lords raided each other's farmers, who fled into the hills or woods for safety. Often a lord's fighting men stayed with him at his large house, but later were given land with inhabitants on it, who became his tenants. The lords were the ruling class and the greatest of them sat in the King's council along with bishops, abbots, and officers of the King's household. The lesser lords were local magnates, who officiated at the shire and hundred courts. Stag-hunting, fox-hunting, and hawking were reserved for lords who did not work with their hands. Every free born person had the right to hunt other game. There was a great expansion of arable land. Some land had been specifically allocated to certain individuals. Some was common land, held by communities. If a family came to pay the dues and fines on certain common land, it could become personal to that family and was then known as heir-land. Most land came to be privately held from community-witnessed allotments or inheritance. Book-land was those holdings written down in books. This land was usually land that had been given to the church or monasteries because church clerics could write. So many thegns gave land to the church, usually a hide, that the church held 1/3 of the land of the realm. Folk-land was that land that was left over after allotments had been made to the freemen and which was not common land. It was public land and a national asset and could be converted to heir-land or book-land only by action of the king and witan. It could also be rented by services to the state via charter. A holder of folk-land might express a wish, e.g. by testamentary action, for a certain disposition of it, such as an estate for life or lives for a certain individual. But a distinct act by the king and witan was necessary for this wish to take effect. Small private transactions of land could be done by "livery of seisin" in the presence of neighbors. All estates in land could be let, lent, or leased by its holders, and was then known as "loenland". Ploughs and wagons could be drawn by four or more oxen or horses in sets of two behind each other. Oxenshoes and horseshoes prevented lameness due to cracked hooves. Horse collars especially fitted for horses, replaced oxen yoke that had been used on horses.