share of the peasantry remained largely the same as it had in the previous century, with around 1/3 of arable land in the hands of peasant smallholders in 1789. A newer trend was the amount of land which came into the hands of bourgeois owners during the 18th century: fully 1/3 of the arable land in France by 1789. The stability of land ownership made it a very attractive investment for the bourgeois, as did the social prestige which it brought. Pivotal developments in agriculture such as modern techniques of crop rotation and the use of fertilizers, which were modeled on successes in Britain and Italy, began to be introduced in parts of France. It would, however, take generations for these reforms to spread throughout all of France. In northern France the three-field system of crop rotation still prevailed, and in the south the two-field system. Under such methods, farmers left either one third or half of their arable land vacant as fallow every year to restore fertility in cycles. This was both a considerable waste of land at any one time which might otherwise have been cultivated, and an inferior way of restoring fertility compared to planting restorative fodder crops. Farming of recent New World crops, including maize (corn) and potatoes, continued to expand and provided an important supplement to the diet. However, the spread of these crops was geographically limited (potatoes to Alsace and Lorraine, and maize in the more temperate south of France), with the bulk of the population over-reliant on wheat for subsistence. From the late 1760s onwards harsher weather caused consistently poor wheat harvests (there were only three between 1770 and 1789 which were deemed sufficient). The hardship bad harvests caused mainly affected the small proprietors and peasants who constituted the bulk of French farmers; large land owners continued to prosper from rising land prices and strong demand. Bread shortages could cause steep price rises, which in turn might lead to mass disruption and rioting. The average wage earner in France, during periods of abundance, might spend as much as 70% of his income on bread alone. During shortages, when prices could rise by as much as 100%, the threat of destitution increased dramatically for French families. The French government experimented unsuccessfully with regulating the grain market, lifting price controls in the late 1760s, re-imposing them in the early 1770s, then lifting them again in