From the 17th through early 18th centuries, tobacco quality in the Carolinas was poor, mainly because of thin soil, so tobacco grown there was typically traded locally for snuff and pipe tobacco. Interstate trade among Piedmont farmers was difficult because North Carolina's main export center was located in Edenton, and goods could be lost, damaged, or delayed on the hard route to the coast with its rocks, narrow waterways, waterfalls, and rapids. Despite a 1679 trade ban, some Piedmont farmers sent their goods north to Virginia because the trade routes were better. In 1731, the tobacco trade ban between North Carolina and Virginia was lifted. At that time, Mecklenburg County was a major trading center in the state, and because Charlotte was the seat of the county court, farmers from near and far regularly brought their goods and crops there. Goods and crops also moved to port cities such as Roanoke, Virginia, Charleston, South Carolina, and Edenton and Wilmington, North Carolina, and from those cities tobacco was exported to Europe, where it was considered a luxury. During the 18th century, European consumers wanted a milder, lighter flavored tobacco than the dark, robust flavor they had been used to, and mild yellow leaves grew fairly well in the Carolina Piedmont because of the thin, less nutrient soil. It is likely that the Polk family grew leaves of this sort between the late 18th and early 19th centuries.