Nov. 27, 2009— -- When Eric and Gloria Sundback began growing Christmas trees more than 50 years ago on a small farm in northwest Pennsylvania, little did they know their passion for raising the "perfect tree" would land them in the history books: four times.
The Shepherdstown, W.Va., couple, now in their 80s, today delivered a precisely 18½ foot Douglas fir to Michelle Obama at the White House, where the tree will stand in the Blue Room throughout the holidays.
"I'm giving the best house in the land a Christmas tree," Eric Sundback said proudly.
"It's always a thrill," his wife said. "Nice to see one of them end up as the White House Christmas tree."
The Sundbacks' trees have won four National Christmas Tree Association contests, including this year's, each time receiving the honor of donating a tree from their farm to the first family.
They delivered their first tree to Rosalyn Carter in 1979, and had two winning trees in the White House during Ronald Reagan's presidency.
This year the couple selected a perfectly shaped, 1,500-pound Douglas fir as a "gift to the White House and American people," Gloria Sundback said.
"This tree was one we had selected to send to the seed orchard," she said. "But when we came to dig this one, they couldn't get the spades down. … He was on a rock, and so we said, 'Well, that's a nice tree, so we'll just leave it there.'"
The Sundback's cut down the tree Wednesday and prepared to transport it to Washington. But they showed little remorse for losing one of their own.
"It's time to do it, it's joy to see them go for Christmas trees," Eric Sundback said. "It's either now or it's toilet paper later."
The Douglas fir joins 15 other trees hand-picked by the chief White House usher and destined for rooms in the White House, including the Oval Office.
Up Close With the First Ladies
Presenting the White House Christmas tree to first ladies is a thrill that has provided a unique opportunity to see the women up close during the years, Gloria Sundback said.
She's excited this year to meet Obama, who shares her passion for gardening. "I think she's doing a great job. … She seems to be interested in a lot of different things in the plant world and growing things," Sundback said. "It's a fresh approach.
"Rosalyn Carter was very outgoing. … She came right out and, boy, she knew who everybody was. She never saw us before, but she had us identified and came right over."
Nancy Reagan, Sundback said, was more reserved. "It wasn't an easy role for her, I don't believe," she said. "But she was very gracious and seemed to have things in command.
"[The first lady] is not an elected job, you're not paid a huge salary for anything. That's a tough job."
For the Sundbacks, creating the perfect Christmas tree is a methodical science that has become for them a passionate hobby. They established their own seed orchard in 1974 and have been in pursuit of seeds from ideal trees ever since.
The duo has traveled the country -- more than 70,000 miles in the Rocky Mountains, they say -- selecting the best trees, picking their seeds and bringing them home to plant in West Virginia.
"Every tree, we know the parents of it on our plantation. And we keep breeding trees and picking out the best," Gloria Sundback said. "We have 'planned parenthood' for Christmas trees."
The ideal tree has a definite needle, deep-green color, strong branches and a consistent angle and length of branches from the trunk of the tree, she said.
Sundbacks: Older Than 80 and Still Planting, Pruning
Eric and Gloria Sundback said they weren't able to do as much field work as they used to in their younger days, but that isn't stopping them from planting more. They love the spirit of Christmas, they said.
And despite his look, Gloria Sundback said, her husband is not exactly trying to look like Santa Clause.
"Everybody thinks he has that beard for his business," she said. "But the truth of the matter is that Eric -- the first generation of a Swedish family -- sunburns terribly bad: one big blister. ... So, in 1968, when the pruning season started, he grew a beard to cover part of his face from the sun."
He has had the beard ever since.
ABC News' David Wright and Sally Hawkins contributed to this report.