For the first time in my life, on the day after Thanksgiving, I went to a tree farm in Waterford, Pennsylvania. As I walked through rows and rows of Fraser firs, looking for the perfect seven-foot-tall Christmas tree for my boyfriend’s family, I couldn’t help but feel pangs of guilt. I love nature, and I feel bad about cutting down an eight-year-old tree just to use it as a decoration for a few weeks.

My family, like most Italians I know, always used a fake tree for Christmas; the same 11-foot plastic fir has decorated our living room since I was a kid. At first, I thought that was better for the environment, since it didn’t kill a tree yearly for decor. But my European sense of superiority took a hit as I did a little bit of research.

Real Christmas trees are probably better for the environment than fake trees, at least from the perspective of their carbon footprints, says Clint Springer, a botanist and professor of biology at Saint Joseph’s University. If you want to get yourself the most environmentally friendly Christmas tree, you should choose one that still has its root ball attached, so you can replant it after the holidays.

Here’s the thing I had never thought of when weighing the pros and cons: Christmas trees are a crop in the US, so they’re grown on farms for the purpose of being cut down. “It's different than deforesting a tropical rainforest for example,” Springer tells The Verge. For every tree that’s cut, farmers are likely replanting four or five new ones, to up their odds that a good, healthy tree will grow for a few years before being cut down again. Tree farms also provide a habitat for wildlife like birds, help preserve open spaces, and contribute to the local economy, Springer says.

Fake trees, on the other hand, are made of plastic and metal, which take up a lot of energy and resources to produce. Artificial Christmas trees can also contain polyvinyl chloride, or PVC, which often uses lead as a stabilizer — not exactly what you want in your house if you have children. If the fake tree is also made in China, you have to calculate the carbon footprint of transporting it all the way to the US. So, to minimize the environmental impacts, you should reuse a fake tree for more than 10 or 20 years, according to the The New York Times.

“I know American consumers,” Springer says, “we don’t keep much for 10 years anymore.” My parents in Italy, on the other hand, are still putting up the same fake Christmas tree we bought in 1995. (One point back for European superiority!)

If you really want to do the planet a favor, you should probably buy a real tree with the roots still attached, Springer says. That way, after the holidays, it can be replanted and the tree can continue sucking up heat-trapping carbon dioxide from the atmosphere, as well as provide a home for birds. But, so-called balled and burlapped trees come with some catches. First of all, they’re heavier, more expensive, and messier than your regular cut tree, says Emily Renshaw, a certified arborist at the International Society of Arboriculture (ISA). That’s because the roots need soil and soil needs water.

In fact, you don’t want your live tree to dry up, or die because of the changes in temperature between the indoors and outdoors. Before placing the tree in your living room, you should acclimate it in your garage for one or two days, and you should keep it indoors for five to seven days max, according to ISA. You should also know in advance what exactly you’re going to do with the tree after the holidays: if you have a backyard where you can replant the tree, you should dig the hole before the ground freezes, and make sure the species you bought is suitable for your area. You can also check if local nurseries, city parks, or schools accept live trees for donation. “You really have to do your homework ahead of time,” Renshaw tells The Verge. “It’s kind of like getting a pet for Christmas.”

Scott Bilmar, of Bilmar Nurseries in Pleasant Valley, New York, said that his nursery used to sell balled and burlapped Christmas trees in the past, but it stopped because he heard too many stories of trees dying. “It’s not a wonderful idea,” he tells The Verge. Still, it’s not impossible. Springer, the botanist, says his backyard in North Central West Virginia still hosts a Christmas tree he planted 35 years ago.

Every year, he buys a cut Christmas tree from a tree farm nearby so he doesn’t have to drive far, thus pumping less CO2 into the atmosphere. After the holidays, he mulches it. In the spring, he uses that mulch as fertilizer for his garden. “It’s a closed-loop system,” he says.

That puts him at peace with the planet — and it puts me at peace with my boyfriend’s family. As far as my parents in Italy are concerned, I’ll tell them to keep using that fake Christmas tree from 1995 until the needles fall off. After that, real Christmas trees only!