dependents, support an urban family home, and fund the owner's public and military career, in the form of cash for bribes and security for loans. Later Roman moralists idealised farming as an intrinsically noble occupation: Cincinnatus left off his ploughing reluctantly, to serve as dictator, and returned once his state duties were done. In law, land taken by conquest was ager publicus (public land). In practise, much of it was exploited by the nobility, using slaves rather than free labour. Rome's expansionist wars and colonisations were at least partly driven by the land-hunger of displaced peasants, who must otherwise join the swelling, dependent population of urban plebs. At the end of the second Punic War, Rome added the fertile ager Campanus, suitable for intense cultivation of vines, olives and cereals. Like the grain-fields of Sicily – seized after the same conflict – it was likely farmed extra-legally by leading landowners, using slave-gangs. A portion of Sicily's grain harvest was sent to Rome as tribute, for redistribution by the aediles. The urban plebs increasingly relied on firstly subsidised, then free grain. With the introduction of aqueducts (from 312), suburban market-farms could be supplied with run-off or waste aqueduct water. Perishable commodities such as flowers (for perfumes, and festival garlands), fresh grapes, vegetables and orchard fruits, and small livestock such as pigs and chickens, could be farmed close to municipal and urban markets. In the early 2nd century Cato the Elder tried to block the illicit tapping of rural aqueducts by the elite, who thus exploited the increased productivity of cheaply bought, formerly "dry" farmland; a law was duly passed, but fines for abuses, and taxes on profits, proved more realistic solutions than an outright ban. Food surpluses, no matter how obtained, kept prices low. Faced with increasing competition from provincial and allied grain suppliers, many Roman farmers turned to more profitable crops, especially grapes for wine production. By the late Republican era, Roman wine had been transformed from an indifferent local product for local consumption, to a major domestic and export commodity, with some renowned, costly and collectable vintages. Roman writers have little to say about large-scale stock-breeding, but make passing references to its profitability. Drummond speculates that this focus on agriculture rather than livestock might reflect elite preoccupations with historical grain famines, or long-standing competition between agriculturalists and pastoralists. While agriculture was a seasonal practise, pasturage was a year-round requirement.