Christmas tree growers are frustrated that politics are delaying a marketing campaign to promote real trees over artificial. Following four years of work to get it passed, the U.S. Department of Agriculture approved the industry-sponsored real Christmas tree campaign in November. But conservatives quickly branded it as "President Obama's Christmas tree tax" and the program was delayed within days of its approval. There are 18 other commodities — like pork and eggs — with similar generic advertising programs. They show anywhere from a two-to-one to a ten-to-one return on investment.