Adrian Higgins

The Washington Post

Old magnolias never die; they just fade away. That seems to be the fate of the most historic tree at the White House, a Southern magnolia planted by Andrew Jackson and now so ancient and fragile that part of it was dismantled last month.

The decision to take down or at least dismember an old tree is neither easy nor always objective, but professional arborists are guided by a risk assessment protocol that brings a rationality to the process. The evaluation assesses the tree’s vigor, the thickness of its sapwood shell, its disease stresses, the state of the roots and the like. Arborists also consider its location and the proximity to what they call “targets” — property and people.

“A tree in the middle of the woods is not a problem,” said arborist Paul Wolfe of Integrated Plant Care in Rockville, Maryland. “In an urban area, that’s some problem.”

The Jackson magnolia could not be less out of the way. It stands between the Rose Garden and the west side of the South Portico, and though sheltered by the executive mansion, it is buffeted by the rotor wash of the presidential helicopter.

Gardeners, by the way, tend to be highly ambivalent about Southern magnolias. These emblems of the Deep South are stately and evergreen and have exquisite blossoms, creamy white chalices surrounding a column of beautiful stamens. The fragrance is sweet and lemony.

But the leaves are tough as old boots, and they drop continually from June until the fall. Also, it is virtually impossible to grow anything else beneath a Magnolia grandiflora.

“It’s a wonderful tree, but in my neighbor’s yard, not mine,” Wolfe said.

There is a prevailing mentality among many homeowners that big old trees are inherently threatening and should be removed. This is sort of like refusing to get on a plane because it can crash.

With the 2012 derecho and other destructive storms before and since, “people are fearful that large trees around their houses might fall,” said Michael Guercin of Branches Tree Experts in Kensington, Maryland.

If you’re worried about limbs or whole trees crashing down, what should you do? I would ask a consulting arborist or one certified by the International Society of Arboriculture to offer an expert opinion on a tree you’re worried about, but an opinion only. A consultation is typically $75 to $150, Guercin said. This removes any impulse to suggest work to generate business.

Dead wood should be removed, but experts will tell you that decay and cavities are not enough to condemn trees. It comes down to the extent of the decay and whether it reaches into the roots, Guercin said.

“A tree with a cavity often responds by growing reaction wood” that strengthens it, said Ed Milhous, an arborist in Haymarket, Virginia. His firm is called TreesPlease. “Anybody who says, ‘There’s a cavity in that tree, it needs to be removed,’ is out of line.”