Two men look at a famed Magnolia tree, at left, planted on the south grounds of the White House by President Andrew Jackson in 1835 has been trimmed, in Washington, Wednesday, Dec. 27, 2017. (AP Photo/Andrew Harnik)

Meryl Gordon is the author of "Bunny Mellon: The Life of an American Style Legend."

On a warm day in September 1961, Rachel Lambert Mellon — known as Bunny — sat on a white bench on the White House lawn, underneath a stately magnolia tree, waiting to meet with President John F. Kennedy. Clad in Balenciaga, her posture ramrod straight, she looked the picture of aristocratic confidence. But in reality, she was anxious.

A month earlier, first lady Jackie Kennedy — Mellon's best friend — had called to alert her that the president was going to ask her to redesign the White House Rose Garden. Hours later when he made the request during a picnic lunch on the beach at Mellon's Cape Cod home, she initially resisted. Yes, she had created magnificent gardens at her estates in Upperville, Va., and the Cape, but Mellon told the president that she lacked the professional training to tackle this historic spot.

"As an amateur, I questioned my ability to design a garden of such importance," she later wrote in an essay for White House History. "Paying little attention to that doubt, he bubbled with enthusiasm, with fascinating details of how he wanted a garden to appeal to the most discriminating taste, yet a garden that would hold a thousand people for a ceremony."

For their first official White House meeting, she had brought along the Harvard-trained Washington landscape architect Perry Wheeler. Waiting for the president, they looked around the garden outside the Oval Office for inspiration, notably the handsome magnolia tree towering overhead. Andrew Jackson planted the specimen in honor of his wife, Rachel, who died shortly after his 1828 election.

Now that nearly 200-year-old tribute to presidential love is in its final days. As CNN reported this week, the Trump White House has decreed that the damaged and decayed Jackson magnolia be torn down. For all the examples of President Trump the philistine, this decision appears to be based on horticultural realities rather than issues of taste. Trump admires Jackson; in January he placed a portrait of the controversial Jackson in a prominent place in the Oval Office.

First ladies often preside over decisions involving the White House grounds and gardens. According to CNN, Melania Trump opted to tear down the tree after reading recommendations by the U.S. National Arboretum and consulting with her staff. One key staffer brings a special sensitivity to the landscaping at 1600 Pennsylvania Avenue — White House social secretary Rickie Niceta, who is married to Bunny Mellon's grandson Thomas Lloyd, knew her well.

When I was researching my biography of Mellon, who died in 2014 at the age of 103, I learned that the Jackson magnolia had been key to her redesign of the Rose Garden. John Kennedy had asked Mellon to create the equivalent of an elegant outdoor stage set for use as a backdrop for ceremonies and entertaining.

Mellon was baffled by how to create a unifying design until she strolled by the Frick Collection in Manhattan on a chilly day and spotted three magnolia trees, stripped of their leaves. "Their pale silvery branches with heavy twigs seemed to retain the light of summer," she wrote.

Installing magnolias inspired by the Jackson tree turned out to be a complex task. After searching for mature specimens, Mellon fell in love with trees in one of most scenic spots in Washington — the Tidal Basin. The National Park Service turned down her request to uproot the trees; White House head gardener Irvin Williams had to pull strings to make it happen.

The Park Service then expressed concerns that digging so deep near the White House to plant the magnolias might disrupt underground cables. "Their only solution seemed to be to abandon the idea of any trees," Wheeler wrote to Mellon. She and Wheeler won that argument.

But the Park Service's concerns proved prescient. On March 31, 1962, a workman with a shovel accidentally severed the connection between the president's office and the Strategic Air Command, which would have allowed Kennedy to launch a nuclear attack. This created a momentary crisis, but Mellon insisted that the president did not complain to her. "This startling experience was handled with calmness; not even the president reprimanded us for the deep digging," she would later write.

Now these magnolias, planted more than a half-century ago, will remain a touchstone to another era. With respect for the historic significance of the Jackson magnolia, the White House hopes to eventually replace its storied boughs with seedlings grown from the original.