In the south, the cotton plantations were flourishing, thanks to the very high price of cotton on the world market. Cotton production wears out the land, and so the center of gravity was continually moving west. The annexation of Texas in 1845 opened up the last great cotton lands. Meanwhile, other commodities, such as tobacco in Virginia and North Carolina, were in the doldrums. Slavery was dying out in the upper South, and survived because of sales of slaves to the growing cotton plantations in the Southwest. While the Northeast was rapidly urbanizing, and urban centers such as Cleveland, Cincinnati, and Chicago were rapidly growing in the Midwest, the South remained overwhelmingly rural. The great wealth generated by slavery was used to buy new lands, and more slaves. At all times the great majority of Southern whites owned no slaves, and operated farms on a subsistence basis, serving small local markets.