When it comes to choosing a Christmas tree some people would not think of having anything other than a real tree, while others feel the same way about artificial ones. The plus point with an artificial tree is you can bring it out every year and there are no shedding needles to contend with. However for that authentic look and smell of Christmas, nothing beats a real tree but for the environmentally conscious which is actually better. Some would think the fake tree as you reuse it and because a real tree is not being cut down but this is not necessarily so.

In the most definitive study of the perennial real vs. fake question, an environmental consulting firm in Montreal found that an artificial tree would have to be reused for more than 20 years to be greener than buying a fresh-cut tree annually. The calculations included greenhouse gas emissions, use of resources and human health impacts.

“The natural tree is a better option,” said Jean-Sebastien Trudel, from the firm, Ellipsos, that conducted the study.

The annual carbon emissions associated with using a real tree every year were just one-third of those created by an artificial tree over a typical six-year lifespan. Most fake trees also contain polyvinyl chloride, or PVC, which produces carcinogens during manufacturing and disposal.

Ellipsos specifically studied the market for Christmas trees bought in Montreal and either grown in Quebec or manufactured in China.

Over all, the study found that the environmental impact of real Christmas trees was quite small, and significantly less than that of artificial trees — a conclusion shared by environmental groups and some scientists.

“You’re not doing any harm by cutting down a Christmas tree,” said Clint Springer, a botanist and professor of biology at Saint Joseph’s University in Philadelphia. “A lot of people think artificial is better because you’re preserving the life of a tree. But in this case, you’ve got a crop that’s being raised for that purpose.” Makers of fake trees argue that the environmental evidence isn’t quite so clear-cut. “If you buy an artificial Christmas tree and reuse it for at least five years, it’s absolutely a green thing to do,” said Thomas Harman, founder and chief executive of Balsam Hill, a maker of premium artificial trees. Harman said that the average amount of car travel by consumers to buy a real Christmas tree outweighed the added energy and pollution costs of buying an artificial tree from China.

The American Christmas Tree Association, the main trade group for artificial tree makers and retailers, says its own study found that it took 10 years of use before a fake tree became better for the environment than a real one, at least in terms of carbon emissions. Close to 400 million trees now grow on Christmas tree farms in the United States, according to the National Christmas Tree Association, which represents growers and retailers of real trees. About 30 million trees are harvested annually. The living trees generate oxygen, help fix carbon in their branches and in the soil and provide habitat for birds and animals, Springer said.

Artificial trees, by contrast, are manufactured almost exclusively in Asia from plastic and metal and cannot be recycled by most municipal recycling programs. After six to 10 years of use, most will end up in a landfill.

Jami Warner, executive director of the American Christmas Tree Association, the group promoting artificial trees, said that neither kind of tree had much of an impact on the environment — “especially when compared to something that most of us do every day, like drive a car.”