Newswise — Christmas trees come in many shapes and sizes, offering consumers an array of choices to make the season bright. Whether your favorite is blue spruce, Douglas fir, Scotch pine or made of PVC (polyvinyl chloride), Clint Springer, Ph.D., a botanist and climate change expert at Saint Joseph's University in Philadelphia, cautions that of the many factors to consider when choosing a holiday tree, impact on the environment should be at the top of anyone's list.

Springer says that although some people consider farm-raised trees wasteful and potentially harmful to the environment, given that they are enjoyed for a brief time before a trip to the curb for trash pick-up after the festivities, the opposite is actually true.

"For the environmentally conscious consumer, a live Christmas tree is preferable to artificial," he says. "An expenditure on a live tree results in a carbon neutral purchase that poses very little environmental threat, while injecting money into the domestic economy."

Springer adds that the most environmentally friendly tree would be raised organically " without the use of chemical pesticides, fertilizers or herbicides " in nearby environs with its roots intact, so that it can be re-planted after Christmas. He says buying from a local grower cuts down on the use of fossil fuels to transport the tree to the seller's place of business, which reduces the amount of greenhouse gases released into the atmosphere.

However, if it isn't possible to "go organic," Springer emphasizes it is still better to buy farm-raised rather than plastic, even considering the use of pesticides by tree farmers. Research from North Carolina State University has shown that the run-off of chemicals to streams by Christmas tree farms does not cause a significant threat to water quality. But the fabrication of synthetic trees is not so benign. Springer notes that making the artificial variety requires an increased use of resources, especially those that are non-renewable " such as petroleum " and also causes the release of harmful greenhouse gases during their production, processing and shipping. "Another huge drawback to fake trees is that eventually, they will end up in a landfill where they will linger in the environment forever, whereas live trees are recycled and made into mulch," Springer explains.

In addition, farmers commonly plant saplings to replace trees sold for the holiday season harvest, which culminates in a zero net exchange of greenhouse gases over the life of each purchased tree, Springer says.

Still, budget-conscious consumers will argue that artificial trees are cheaper in the long run since they can be used for multiple years. But Springer says the choice to go live is a boon to the economy, because the industry brings in over $500 million annually, according to the U.S. Census Bureau. "For example, Pennsylvania boasts more Christmas tree farms than any other state " while most artificial trees are produced in China," he says.