This Christmas, Vicki Freshley will proudly show off her prized fake fir.

In her eyes, it’s a beautiful thing, as nice as any real Christmas tree — nine feet tall, emerald and fluffy, and decked out with so many eye-popping trimmings that her brother stopped in his tracks when he saw it and said, “Oh my God.”

But in the eyes of many environmentalists, Freshley could have made a better choice than buying that artificial tree last year at a Costco near her home in Gaithersburg. Even tree huggers are encouraging Americans to go out every December and buy a real tree from a lot or go to a farm, cut one down, and drag it home because tree farms are good for the atmosphere.

Artificial trees have been gaining ground in American living rooms — 50 million fake trees vs. 30 million fresh ones, according to the two competing industry groups, the long-standing National Christmas Tree Association (which supports real trees) and the more recently formed American Christmas Tree Association (defends artificial trees).

But the real trees aren’t going down without a fight. The battle comes to a head on Saturday — two weeks before Christmas — the Christmas trees’ own Black Friday, expected to be the highest-traffic day in tree buying. And at the forefront of the argument is which kind of tree is better for the environment.

For a symbol of yuletide cheer, the tree brings out some pretty hostile rhetoric. One side’s Web site says fake Christmas trees were invented as oversize “green toilet brushes.” The other’s claims that “after two weeks of being indoors, a live Christmas tree emitted significant amounts of mold spores.”

Each side offers what it considers compelling evidence.

Real fir — along with pine and spruce — has benefits beyond a fresh smell that says Christmas, supporters say. The trees’ purchase encourages farmers to keep planting acres that absorb carbon dioxide from the air, soak up storm-water runoff full of nutrient and sediment pollution before it pours into waterways such as the Chesapeake Bay, and provide habitat for wildlife.

The real trees also have a smaller carbon footprint than ones made with plastic and shipped mostly from factories in China, said Stephanie Flack, Potomac River Project director for the Nature Conservancy. “This time of year, while people are thinking of gifts they get from under the tree, they should be thinking about the gift from trees,” Flack said.

But the American Christmas Tree Association would say that Freshley’s fake-tree purchase was the greener choice. The group cites a study to support its view that fake trees have a lower carbon footprint — if consumers hold on to fake trees for six to 10 years — considering the energy it takes to chop, water and transport fresh trees annually.

The study did not say how long the typical tree buyer holds on to faux firs. But at any rate, the group says, most fake trees go back into a box, rather than a street curb for pickup by a truck.

Real trees have other drawbacks: Some, such as the Fraser fir, are susceptible to a deadly water mold that can infect other trees, according to the Sierra Club, and nearly all firs are doused with pesticides to kill invasive pests such as the Douglas fir beetle.

Last year, retailers sold about 13 million artificial trees, according to the American Christmas Tree Association. About 85 percent are imported from China, and concerns have been raised about the labor conditions under which some are produced.

More than 95 percent of real trees for the U.S. market are grown in the United States.

The USDA gave up a short-lived plan for a “Got Milk”-type campaign to support real trees after it drew complaints that the government was putting a tax on Christmas. The government approved a marketing campaign for real trees that would be funded by a 15-cent charge to larger growers for each tree sold. Commentators including Rush Limbaugh, along with the Heritage Foundation, derided the plan as a Christmas tree tax, and the administration put it on hold.

In the United States, about 15,000 farms grow 400 million trees and employ 100,000 full-time and part-time workers, according to the National Christmas Tree Association. The Maryland Christmas Tree Association lists more than 70 member farms on its Web site. The Virginia Christmas Tree Growers Association’s Web site says state nurseries make about $50 million yearly in Christmas-related sales.

It can take four to 15 years to grow a tree of typical height, with an average growing time of seven years.

A small fraction are cut for customers over the holidays, leaving 90 percent to suck up carbon and to develop bark, sap and pine needles the rest of the year. Environmental groups estimate that an acre of firs absorbs more than 11,000 pounds of carbon dioxide annually.

At Mount Hope Farms in Hagerstown, Dan Blickenstaff and his wife, Sharon, plant about a thousand firs per acre on a 15-acre nursery.

Blickenstaff wouldn’t say how many trees he’s sold this season, but “my wife keeps track on a weekly basis. It’s only nine short of last year. We sell between 1,000 and 2,000 trees a year. It’s going real well.”

At one time, the Blickenstaffs purchased trees from a middleman who got them from farms in Oregon and Washington.

“We’d go to a lot and see trees dying,” Blickenstaff said, because they were no longer fresh. “That’s what gave the real tree a bad name.”

On an unseasonably warm night in December, Hugh Rodell, co-owner of North Star Christmas Trees in Beltsville, prepared the lot for Saturday.

“We often wonder if the real tree is going to go the way of the buggy whip,” he said. “I hope not. There’s always a love for the natural.”

Families strolled through the corner lot redolent of pine and fir. The holiday tunes were cheery, and round bulbs hung from poles.

“We’re trying to sell an experience,’’ Rodell said. “We want it to look like you’re walking through a Norman Rockwell painting.”

Freshley, however, was very clear about why she bought her plastic tree.

“I love it because . . . I don’t have needles on the floor,” Freshley, who sells stationery, said of her tree while shopping for decorations with her son, Shawn, at a large hardware store in Gaithersburg. “I can take it apart myself. I don’t have to wait for my husband to drag it out of the house.

“I had my old tree for 10 years before I bought the new one,” Freshley said, which is what the American Tree Association recommends.

But she had a flash of doubt about her purchase when told of the real-vs.-fake-tree debate. “It sounds so insensitive” to buy a fake, she said.

But then she thought back to the smiles the artificial tree inspired. Freshley cheerfully recalled the look on her brother’s face when he visited her home. “He said it’s beautiful,” she said. “He said, ‘Can you decorate for us?’ ”