 Additionally, the Indians were pushed back in several campaigns, allowing for the expansion in size of the plantation, and another growth of population which put additional pressures on land and small farms.Slowly, over the remaining century and into the early 18th century, the farms turned to the valuable but land-depleting sugar and tobacco crops.As the soil depleted, requiring more and more land, large numbers of slaves were brought into work the mortgaged land cheaply, thereby creating an economy of capital centralization.