While the first Christmas tree farm may have appeared as early as 1901, Christmas tree production in the United States was largely limited to what could be harvested from natural forests until the 1950s. Among the important Christmas tree producing areas in the U.S. are Wisconsin, North Carolina, Pennsylvania and the Pacific Northwest. In 2002 Christmas tree production in the United States totaled 20.8 million trees and the U.S. was one of the world's leading producers of natural Christmas trees. That same year, Pennsylvania was the top producer in the United States.