Joan Maloof is the founder of the Old-Growth Forest Network, which seeks to protect remaining pockets of virgin forest. (Adrian Higgins/The Washington Post)

The vista from the steps of Arlington House offers one of the most spectacular views of Washington. The scene unfurls, from the sloping lawns of Arlington National Cemetery to Memorial Bridge to the Lincoln Memorial and on to the Mall. The architectural geometry is leavened by the snaking Potomac River.

But I have huffed and puffed my way up to this high ground to see something more ancient and, in its own way, defining of the nation’s history. Joan Maloof is waiting to show me the other side of the mansion, a pocket of forest known as the Arlington Woods. Only 12 acres remain of what was once a sylvan 600 acres, part of the 1,100-acre estate owned by G.W.P. Custis, the adopted grandson of George Washington (and father-in-law of Robert E. Lee).

Entering the woodland is tricky; there are no easy trails, and we have to leap across a drainage swale. But once we are in the heart of this forested dell, the sounds of the riding mowers and the tour trams and even the passenger jets are muted. They are replaced with shrieks of blue jays and the white-noise rustle of the wind through the leaves. Maloof, who is 61 and trim, with piercing slate-blue eyes, seems to both relax and come alive in this place. She blithely clambers onto a huge fallen trunk and uses it as a pixie perch to look up to the forest’s light-filtering canopy.

As an ecologist and founder of a group called the Old-Growth Forest Network, Maloof is a pro at reading this woodland. The canopy is high — the trees reach to 100 feet or more — but this place might be a mere century old. One clue that it is far older is the proximity of enormous trees of different species. We find a white oak close to an American basswood, and then a tulip poplar. She tries to gauge its trunk size by wrapping her arms around maybe a third of its circumference. Maloof is, unabashedly, a tree-hugger.

According to Maloof’s organization, old-growth forests support a much greater level of biological diversity than woodland that has been disturbed by settlement. (Adrian Higgins/The Washington Post)

There are other signals of the virgin forest: She points out the way a thick limb has changed direction to form a looping arch high in the sky. The bough is as thick as the trunk of an old tree. It changed direction as a result of some abrupt shift in light patterns, probably when a neighboring tree fell down. “There’s a wonderful term for this,” she says. “Sinuosity.”

The most obvious sign that this woodland has been left unmolested is that there are several old trees now fallen, forming great horizontal columns, as if Samson had passed this way.

She leads me to a fallen white oak more than three feet in diameter. “It can take one of these trees as long to decay as it took to grow,” she says. Before it returns to the soil, the dead oak is anything but lifeless; it provides a home to countless generations of insects, plants, amphibians, birds, reptiles, wee mammals, fungi and microbes.

Maloof is the author, with nature photographer Robert Llewellyn, of a new book about the Eastern deciduous forest, "The Living Forest," which marries her lyrical text with his images. Llewellyn is a master of revealing the intricacies of the small-scale elements of such big creatures, things such as the winged fruit of the maple or the male catkins of the red oak, spilling over their twigs like waterfalls.

The book comes on the heels of another of Maloof's, "Nature's Temples," which more squarely looks at the precarious state of virgin forest, which once covered much of what is now the eastern half of the United States and the Pacific Northwest. East of the Mississippi, about 1 percent survives in ever smaller and more isolated pockets as woodland that has not been cleared for agriculture and settlement, or simply harvested for its wood.

Most of the established woodland we see today is second growth, originating a century or more ago. The untouched forest, she says, is much richer, not just in ancient trees but in the biodiversity it supports. Surveys have found almost 500 salamanders per acre in the old-growth forest, compared with fewer than 100 in younger forests. Some species of insects, lichens and fungi are found only in old-growth forests.

Maloof says that if she had settled in a thick and seemingly eternal forest, “I would definitely have built my log cabin and I would have cleared space for food, but we went wrong with industrial forestry way back in the 1800s.”

Timber fueled the growth of the cities and became in itself big business. We are all complicit. If you live in a stick house, the lumber probably came from softwood plantations that replaced old-growth forests.

To me, the old-growth forest is as much an idea as a place. It exists not for our utility or even our pleasure, but as an ecosystem that would carry on if humans went away (and certainly would be less threatened if humans went away). This idea of forest for its own sake takes a conscious shift in our thinking, away from the belief that the world can enjoy reality only if we can experience it.

Back in the Arlington Woods, I can’t help thinking of the trees as being in some kind of communion. As we come to understand that trees are connected by vast, slow-growing networks of fungal strands between their roots, the realization brings a keener sense of the trees as a community. If they do communicate with one another, chemically at least, it is tempting to anthropomorphize these stately survivors and to share their pain when one lifelong companion is toppled or felled.

Even publicly owned woodland is under constant threat, from highway building and the like. Maloof says there are 24 counties in Virginia where there’s “not a single protected, open-to-the-public forest.”

She lives in Berlin on Maryland’s Eastern Shore and says she created the Old-Growth Forest Network for the simple reason that the trees “have no voices. They can’t write, they can’t speak, vote, write checks. They are mute, they just sit there and take whatever happens. It’s up to the humans to take care of them.”

She spent time in Maryland forests in her 30s searching for rare native plants. Later, as a doctoral candidate and teacher, she became more immersed in the woodland and its sense of fragility.

In time, she came to see that the forest does speak to those who listen. “It’s more than just the science and the beauty,” she says. “There is something mysterious and mystical about it.”

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