the prosperity of most towns depended on agriculture. called the "granary of the empire", north africa, according to one estimate, produced one million tons of cereals each year, one-quarter of which was exported. additional crops included beans, figs, grapes, and other fruits. by the second century, olive oil rivaled cereals as an export item. in addition to the cultivation of slaves, and the capture and transporting of exotic wild animals, the principal production and exports included the textiles, marble, wine, timber, livestock, pottery and wool.