Dauphin County (WHTM) Here at the Boyd Big Tree Preserve in Dauphin County, a very special harvest is underway. Biologists Stephen Hoy of the American Chestnut Foundation and Noah Vincent of Penn State are harvesting chestnuts.

But they’re not looking for something to roast on an open fire. This grove is part of a long-term effort to restore a national treasure – the American Chestnut.

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“The trees were used for everything from lumber, to creating tannin for tanning leather, to a food source, not just for humans, but for various livestock over the winter,” explains Hoy.

“Folks would come out to the country from big cities and go “chestnuting”. And so they would come out specifically to harvest wild American chestnuts to take home and eat, as well as folks purchasing them on street corners where they were fresh roasted.”

Chestnuts trees were huge – really huge. Trees one hundred feet tall were not uncommon. They were a huge portion of Pennsylvania’s forests as well.

“There are certain areas where one in three trees was an American chestnut,” says Hoy. “One In four trees across the state was the average.”

But in the late 1800s, foreign chestnut trees were imported. They brought with them a horrible disease.

“This was a fungus called Cryphonectria parasitic,” explains Hoy. “It’s responsible for Chestnut blight. The spores proceed to kill off the cambium layer, the layer under the bark that’s responsible for the flow of nutrients up and down the stem. And it girdles that area, and then everything above that point in the tree dies off.”

The stump below the infected area remains, trying to regrow. It’s estimated there are over 430 million stems from the trees trying to push their way up.

“But a majority of those are less than one inch in diameter,” says Hoy. “So they’re not producing flowers. They’re not producing burrs like the some of the trees here are. So they’re they’re not carrying forward their role in the ecosystem. They just kind of exist in the understory, until one of two things happens. Either the root system becomes depleted and the tree dies completely, or there’s a disturbance in the canopy that allows the trees to take advantage of full sun, get above the competition, and hopefully produce flower and seed for a few years before the blight infects it, and it returns to that kind of suppressed state in the understory.”

Efforts to save the chestnut began as early as the 1920s. In the 1980s the American Chestnut Foundation started a program to restore the tree across its range, using a time-tested agricultural practice of back-crossing, Hoy pointed out a part of the grove where one can see some of the results.

“So this is a straight Chinese chestnut tree,” he said, pointing to his left. Then, pointing to the right, “This tree is the result of an initial cross between a Chinese tree and an American chestnut. And that’s the first step in the American Chestnut Foundation program. By doing that you’re hoping to take the resistant portion of the Chinese Chestnut, and impart that into the American Chestnut.”

Part of the process is to collect chestnuts for study, which is why Hoy and Vincent are pulling down Chestnut burrs from the trees.

“We typically do one tree at a time just so we can ensure that we have it labeled,” says Noah Vincent, “And we know the genetics of that tree. Sometimes if we get there too late and there’s a bunch of chestnuts on the ground, then we just have to give that a different label and say, okay, that’s from one of these trees.”

They have to hurry. As Vincent explains, the locals want their fair share. “As soon as they start opening on the trees, every animal and critter out there wants to get to them. Blue Jays love them, deer, as soon as they hit the ground, turkey, dogs, you name it, they’ll be right after the chestnut.”

The chestnuts collected here will go to Penn State. What happens next?

“We’re very connected with different organizations that work with chestnuts, too,” says Vincent. “A lot of them we’ll send out to other organizations that are also working for blight-resistant chestnuts. Some of them will plant directly into our orchard at Penn State and some of them we’ll use for other different experiments, depending on what we’re looking at.”

The American Chestnut Foundation and Penn State are just two of many organizations working on the chestnut blight problem. A lot of progress has been made, but Stephen Hoy cautions that this is a long-term effort that won’t end, even when 100-foot-tall chestnut trees start to reappear.

“There’s not a definitive timeline for when we’re going to have a solution. And even once we get a product that can be distributed on a broader scale, you’re looking at many years before we can even start to make an impact on the total original range that the chestnut used to occupy.”