Growing Pains

Growing Pains

Some projects require a lifetime of patience. Take, for example, the attempt to rescue the American chestnut tree.

For 14 years, Dr. Phil Arnold of Woodbridge has been helping in the effort to save the nearly extinct native tree that once dominated forests from Maine to the Carolinas, but his interest in its survival dates all the way back to a childhood hike in the 1950s. When he spotted some chestnut seedlings sprouting from a stump, he learned from his father that they, like most American chestnuts, were doomed to die from a fungus that had attacked the entire population. Scientists, his father assured him, were working to figure out how to save them.

sponsored by

United Way of Greater New Haven

They’re still working. Arnold’s contribution to that work resides within a tall wire fence on Woodbridge town property near the Fitzgerald Tract Trails, where 15 American chestnuts are doing their best to grow. They’re the last remaining trees from an orchard of 430 that Arnold planted from seed in 2006 with the help of his farmer nephew, Keith Arnold, and the late Bob Gregg, then-president of the Woodbridge Land Trust. Under the direction of The American Chestnut Foundation, which owns the trees, Arnold hand watered the seedlings and nurtured them through their first years, hoping a few might be resistant to the deadly fungus.

The blight that threatens their existence was discovered in 1904, was spreading out of control by the 1920s and, by 1954, had destroyed 4.3 billion of the majestic trees that, at maturity, could reach 80 feet tall with a trunk too large to reach your arms around. Only a few pockets of American chestnuts remain in Maine and Wisconsin—most likely because their isolation has protected them from infection.

Those 430 seedlings that Arnold planted over a decade ago were all “back-crossed” with a resistant Chinese chestnut; the third-generation seedlings retained about 94% of their American genome. Every one of them, including the 15 that remain standing, were infected within two years. “Do I think the <14> years I put in with not much success were worth it?” Arnold asks. “Yeah, I do, and I’d do it over again… It was a step in the right direction. We still have a ways to go.”

Along with Bryan Pines, current president of the Land Trust, we took our time walking across the acre-and-a-half orchard to check on the trees one humid July morning. Arnold, a retired physiatrist—a specialist in rehabilitation—was himself recovering from knee surgery and navigated the uneven, grassy surface using a cane. We paused at one tree to observe its elongated, sawtooth-edged leaves and the long, fingerlike tufts called catkins that are its male pollinators. The female part of the plant is tiny and spiked to capture the pollen. From it, the tree will grow large, spiky burs that contain its seeds—the eponymous chestnuts, usually two to a bur in the American variety. Arnold poked at one old bur in the grass beneath the tree with the tip of his cane. It was split open in four segments, empty inside. This particular tree, Number 105, bore well over 200 nuts last year, he says.

That fact makes it sound like a healthy tree. What’s not so healthy are the gashes and scars at intervals up the trunk of this chestnut and its neighbors, where it has put up a fight against the fungus. On a scale of 0—not at all resistant—to 5—full resistance—these trees register around 3 or 3.5, Arnold says. One of those scars is the result of an experimental injection of the fungus several years into the orchard project in order to look for resistance. The rest are the result of natural exposure to the spores, which, Arnold says, are “everywhere.”

“It’s working very hard to wall it off,” Arnold says of the tree, “but even though it’s trying to do that, you can see there’s dead branches in there, so… I don’t know how long it’s going to be around.”

About the same time as Arnold was planting the Woodbridge orchard, one of seven in the state, researchers at the State University of New York College of Environmental Science & Forestry (SUNY-ESF) in Syracuse were working on a different solution to the chestnut problem: genetic modification. They inserted a gene from wheat into the American chestnut genome, which allows an enzyme to detoxify the oxalic acid produced by the fungus. This oxalate oxidase gene (OxO) leads to cankers that are “small and superficial” rather than deep and deadly, according to an article in the journal Chestnut. The new genetic line, dubbed ‘Darling 58,’ is currently under review by federal agencies.

Meanwhile, Sandra Anagnostakis, a researcher at the Connecticut Agricultural Experiment Station, had for decades been taking a different approach, testing a virus known to inhibit the growth of the fungus. At CAES’s Lockwood Farm in Hamden, she treated 75 infected American chestnut trees with the virus. Ultimately, when the treatment was ended, “about half of the trees survived, and other half died back to the ground,” according to another Chestnut article. “Some resprouted and continued to grow, while others succumbed entirely to the virus.”

The next chestnut project the Woodbridge Land Trust has its eye on, Pines says, is a seedling orchard, which would require more space and a 40-year commitment. Though it didn’t produce any healthy trees, Woodbridge’s existing orchard continues to provide what Arnold calls “residual stuff that we can turn back to and look at genetically and otherwise sometime in the future.” The orchard serves another purpose as well: education. For a few years, Beecher Road School third-graders walked down to see the trees and learn more about them. And Arnold says walkers often stop along the fence to ask questions. A sign offering pictures and diagrams explains the work of the orchard when no one is around to talk.

In the meantime, nature marches on. The chestnuts now face another threat: Phytophthora cinnamomi, a water mold that attacks their roots. At the same time, ash trees that filled the gaps left in the forest by dead chestnuts are fighting their own battle against a deadly beetle, the emerald ash borer.

It’s enough to discourage the most passionate of tree-lovers, but Arnold and Pines remain undaunted. “We’re doing this and we’re looking towards the future,” Pines says. “Some people expect things to happen overnight… You have to plant a seed and then get the fruit years later.”

Woodbridge Land Trust Chestnut Tree Orchard
Along Beecher Rd south of Center Rd, Woodbridge
Fitzgerald Tract Trails Map | Woodbridge Land Trust

Written and photographed by Kathy Leonard Czepiel. Image 4 features, from left, Bryan Pines and Phil Arnold.

More Stories