construction to avoid buildings developing cracks that would give animals and weevils access to the grains. Press rooms, he advised, should be warm receiving light from the south to prevent the oil from freezing, which makes oil spoil faster. Land Columella describes land as being classified into three types of terrain which he calls champaign (sloping plains), hills with a gradual but gentle rise, and wooded, verdant mountain highlands. Of soil, he says there are six qualities: fat or lean, loose or compact, moist or dry. The permutations of these qualities producing many varieties of soils. Columella quotes Vergil's comment that loose soil is "what we rival when we plough". Of the most preferred types of soil he says the best is fat and loose soil that is the least costly and most productive, then fat and dense which is productive though requiring more effort, and after these are the moist soils. Farming practices In the 5th century BC, farms in Rome were small and family-owned. The Greeks of this period, however, had started using crop rotation and had large estates. Rome's contact with Carthage, Greece, and the Hellenistic East in the 3rd and 2nd centuries improved Rome's agricultural methods. Roman agriculture reached its height in productivity and efficiency during the late Republic and early Empire. Farm sizes in Rome can be divided into three categories. Small farms were from 18–108 iugera. (One iugerum was equal to about 0.65 acres or a quarter of a hectare). Medium-sized farms were from 80–500 iugera. Large estates (called latifundia) were over 500 iugera. In the late Republican era, the number of latifundia increased. Wealthy Romans bought land from peasant farmers who could no longer make a living. Starting in 200 BC, the Punic Wars called peasant farmers away to fight for longer periods of time. This is now disputed; some scholars now believe that large-scale agriculture did not dominate Italian agriculture until the 1st century BC. Cows provided milk while oxen and mules did the heavy work on the farm. Sheep and goats were cheese producers and were prized for their hides. Horses were not widely used in farming, but were raised by the rich for racing or war. Sugar production centered on beekeeping, and some Romans raised snails as luxury food. The Romans had four systems of farm management: direct work by owner and his family; tenant farming or sharecropping in which