PORTLAND, Ore. — It's an annual question: Should you get a real tree or a fake one?

According to Oregon State University Christmas tree specialist Chal Landgren, buying a live tree is better.

For one, while the trees are growing, they are producing oxygen and storing carbon.

They're also sustainably reproduced. When one is chopped down, most often a new one is planted in its place.

Also, once the holidays are over, those trees are put to good use.

"I'll tell you the natural tree is going to be far better for the environment because it's totally recyclable," said Landgren. "At the end of the day when you're getting rid of the tree after Christmas there's plenty of service clubs, etc. that will come and pick up your tree and mulch it or use it for stream bank habitat."

But a study sponsored by the American Christmas Tree Association found that if you buy one artificial tree and use it for more than eight Christmases, that is actually environmentally friendlier than purchasing 8 real trees over that period of time.

On its website, the American Christmas Tree Association says they are a non-profit which represents retailers of both real and artificial trees.

The study took into consideration things like greenhouse gas emissions, water and energy use.

But if real is the way you want to go, Landgren said you should try to buy locally grown trees, something that's pretty easy to do here in the Pacific Northwest.

And when you're done with it, recycle it.

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