With the demise of wooden ships, those uses of pine resin ended, but the industry remained vigorous as new products created new markets. First extensively described by Frederick Law Olmsted in his book "A Journey in the Seaboard Slave States" (1856), the naval stores industry was one of the economic mainstays of the southeastern United States until the late 20th century. Despite a rapid decline of the gum naval stores industry in the last quarter of the 20th century, a few places in the southeastern United States still rely on it as a major part of their livelihood.