Two of the three co-authors of “Philadelphia Trees,” Edward ‘Ned” Sibley Barnard, of Chestnut Hill, and his daughter-in-law, Catriona Bull Briger, a landscape architect who lives in Wyndmoor, admire one of the countless magnificent trees in Wissahickon Park. The third co-author is Paul W. Meyer, director of Morris Arboretum. (Photo by Elizabeth Coady)

by Elizabeth Coady

The assignment: to interview the author of three essential field guides on trees. If ever there was a legitimate excuse to ask the perennial interview question, ‘‘If you were a tree, what kind of tree would you be?’’ it’s now.

So I asked Edward ‘Ned” Sibley Barnard, the author of “New York City Trees,” “Central Park Trees” and most recently, “Philadelphia Trees,” what kind of tree would he choose to be, and he didn’t miss a beat.

“I might very well want to be an American beech,’’ said the former managing editor of Reader’s Digest. “Because an American beech has a clonal colony, it always has smaller beeches around it. And when that beech dies — because they’re all clones, they’re all connected, they’re all totally related to each other — one of these little trees knows that the big one’s dying. And so it grows up and gets bigger.

“And some of these beech colonies … may be thousands of years old. So it’s a great way to sort of live on and with guaranteed progenitors that are directly related to you.”

Barnard, 82, who has a combined 17 progenies of his own counting children and grandkids, has thought a lot about trees, mankind’s stalwart partners-in-time.

The Harvard graduate spent nearly three decades in publishing and another 13 years running The Gazebo, an American homes furnishing company, before returning to publishing to edit nature books. He eventually decided he wanted to write his own book and spent a lot of time walking metropolitan New York gazing upward at trees.

The result was “New York City Trees,” the 2002 guidebook to the city’s “oldest, strangest, most beautiful trees’’ which garnered rave reviews on Amazon. “I will never look at trees in the same way,’’ gushed one reviewer. “Well written by an expert who loves his subject,’’ another opined.

Barnard followed that guide with “Central Park Trees and Landscapes: A Guide to New York City’s Masterpiece.” An accompanying map delineating nearly 20,000 trees in the park was touted by the New York Times as a “labor of wonder.’’

So it’s no surprise that when Barnard arrived in Chestnut Hill in 2009 with his wife Pauline Gray, he brought with him his obsession with trees and penchant for looking up. He also connected with two other local tree huggers, daughter-in-law, Catriona Bull Briger, a landscape architect who lives in Wyndmoor, and Paul W. Meyer, director of the Morris Arboretum. The result is “Philadelphia Trees,” a 280-page, 1,000-plus photo field guide to Philadelphia timber on which the three collaborated.

This stately beauty is Castor-Aralia, the “sentinel tree” outside the gateway to the Japanese Shofuso House in Fairmount Park. Its leaves resemble maple leaves, but it has braided bark and grows black berries from clusters of white flowers, which is very uncommon.

Barnard and Briger will talk about their book and meanderings through area woodlands at the Chestnut Hill Library on Wednesday, Jan. 16, 6 p.m., in the first of a series of lectures planned by the Friends of the Chestnut Hill Library. The authors will be selling copies of their book, divided into sections on “the best places’’ to see trees, “50 Philadelphia great trees’’ and a “tree guide” identifying 168 tree species for amateur dendrologists.

In between producing his first two books on New York trees, Barnard worked at the Tree Ring Laboratory of the Lamont-Doherty Earth Observatory at Columbia University, helping to process and record 2,000 tree cores, essentially pencil-thin strips of wood removed from trees, to determine their ages and the effects of climate on them.

“One of the big things that Catriona and I sort of enjoy about Philadelphia is that there are so many big old trees,’’ Barnard said during an interview at the Chestnut Hill Coffee Company one December afternoon. “There are so many that people don’t even notice them. I can go down my street, Crittenden Street, walking to the coffee shop, and I can see five trees that if they were in New York City, would be among New York City’s five great trees. But in Philadelphia,, people hardly notice them because they’re so used to these big old trees. Philadelphia isn’t as rich as New York, and real estate isn’t as valuable. In New York everything gets torn down and rebuilt.”

The consequence of more inexpensive land is a bounty of woodlands, leading Philadelphia to be dubbed ‘‘America’s Garden Capital,’’ according to an organization of the same name that heralds the region’s “rich tradition of public gardens, arboreta and historic landscapes.’’

“There’s this whole consortium of about 30 gardens, arboretums in this greater Philadelphia area that have banded together because there’s so many old historic estates with amazing gardens and tree productions here,’’ said Briger, 45, who is married to Barnard’s stepson, Sam. Barnard had four children with his first wife, Carolyn, who died of breast cancer.

For the record, Briger won’t say what kind of tree she’d like to be, but a favorite is the ginkgo, an ornate deciduous evergreen from Asia that has been found in fossils dating back 270 million years, according to Wikipedia.

Chestnut Hill resident Edward “Ned” Barnard is one of three collaborators on “Philadelphia Trees: A Field Guide to the City and the Surrounding Delaware Valley,” published by Columbia University Press. (Photo by Pauline Gray)

“I like that it’s so unique, and they get huge, and they’re beautiful,’’ said the mother of two. “And when they’re young, they’re like kind of gangly little teenagers. And then they grow up in these huge beautiful majestic trees, which I like.’’

One of the favorite areas for father and daughter-in-law to admire trees is the Andorra Natural area, off Northwestern Avenue in the Wissahickon Valley Park, which retains horticulture evidence of being a tree nursery in the 19th and early 20th centuries. As a result, the woods there contain trees nonnative to Pennsylvania such as Chinese toons, Korean evodias, Japanese and Norway maples as well as native beeches, birches and oaks.

A map of the area in “Philadelphia Trees” depicts 23 notable sightings here, including a 150-year-old European Beech planted by Richard Wistar, who placed it as part of an allée intended for a never-built estate. The beech, or Fagus sylvatica, was designated a state champion by the Pennsylvania Forestry Association in 2006, one of 1717 Pennsylvania trees that holds that designation.

Barnard and Briger hope the guidebook encourages Philadelphians to put down their phones and explore the natural beauty of area woods.

“Ned has this joke he calls it CPDS — cellphone dependency syndrome,” said Briger. “And so his joke is that our book is like an antidote to that.’’

“It doesn’t need batteries,’’ said Barnard. “It brings you into the present because you’re looking at something real, trying to compare it, instead of looking at a little screen.’’

Barnard’s books can be obtained through Barnes & Noble, Amazon and Morris Arboretum’s Shop.