Decades before the American Revolution of 1776, Jesse Fish, a native New Yorker, retreated to an island off St. Augustine, Florida, to escape unhappy family situation. In a time he became Florida's first orange baron and his oranges were in great demand in London throughout the 1770's. The English found them juicy and sweet and preferred them to other varieties, even though they had thin skins and were hard to peel. There would probably have been other successful commercial growers before Fish if Florida had not been under Spanish rule for some two hundred years. Columbus first brought seeds for citrus trees to the New World and planted them in the Antilles. But it was most likely Ponce de Le6n who introduced oranges to the North American continent when he discovered Florida in 1513. For a time, each Spanish sailor on a ship bound for America was required by law to carry one hundred seeds with him. Later, because seeds tended to dry out, all Spanish ships were required to carry young orange trees. The Spaniards planted citrus trees only for medicinal purpose, however, they saw no need to start commercial groves because oranges were so abundant in Spain. What is the main topic of the passage?