OXFORD, Ohio – Cashews, peanuts, hazelnuts, pecans, almonds, acorns and walnuts are among the most popular edible nuts found and devoured in the United States. They’re plentiful, too.

The tender meat of the chestnut has a slightly sweet flavor. They’re oftentimes roasted, giving them a spongy rather than crunchy texture. Sadly, the chestnut tree with its tasty nut is on the brink of extinction.

Roughly 100 years ago, nearly four billion chestnut trees stood guard down the spine of the Appalachian Mountains from Maine to Georgia. They were about a quarter of the trees in the forest, and their range extended west into central Ohio, to the southern tip of Indiana and into Kentucky.

As pioneers poured over the Allegheny Mountains in the 1780s and began settling eastern Ohio, they passed under the canopy of millions of American chestnut trees, those with mammoth brownish-gray columns of bark towering 100 feet in the air. They were nutritious and delicious. There were so many, legend had it that the early settlers could walk for miles on a carpet of chestnuts.

Then, around the turn of the 20th century, a blight arrived with imported Asian chestnut trees and infected the native trees.

“It was known as the perfect tree,” said Carolyn Keiffer, a botany professor at Miami University’s Middletown campus in Ohio. “Everyone loved the chestnut. The pioneers needed the chestnut. Even today, it makes everyone smile.”

Keiffer is president of the Ohio chapter of The American Chestnut Foundation (TACF).

The wood itself sported a coarse grain and a range of colors. And there was a lot of it. The trunks, at their base, could exceed eight feet in diameter. Chestnut wood was almost as strong as oak but with half the weight. It was easy to work with. Pioneers used it to build their cabins and barns, and, because it was rot-resistant, it was a “must have” for foundations and floors. Leftover wood was made into bed frames, cabinets, tables and chairs.

“It’s a good early example about how transportation is killing the world,” said Brian McCarthy, a professor of ecology at Ohio University and Keiffer’s former instructor. “We’re seeing it not only with the emerald ash borer and the Asian longhorn beetle. Imported insects, invasive plants, and pathogens are carried here, and the native ecosystem has no way to defend itself.”

An effort is being made to reverse this trend in an attempt to revive the chestnut tree. Stephen Rist, who manages the Ohio Department of Natural Resources (ODNR) District 4, is beginning his scientific work and planting 2,000 chestnut seedlings in southern Ohio at Hocking Hills State Forest.

Rist has armed himself with chestnut hybrids: 15/16th American and 1/16th blight-resistant Asian. It’s a crossbreeding experiment, one of three strategies TACF is employing in what’s already a decade-long effort to restore the tree. The foundation calls it the 3BUR strategy, which stands for breeding, biotechnology and bio-control united for restoration. 

The saplings are encased in nearly opaque 5-foot-tall white tubes, but their branches are starting to poke out the top. They aren’t sick yet, but they’re sharing their environment with their killer.

“The fungus is everywhere. It’s probably on the soles of our shoes,” Rist said.

Keiffer introduced McCarthy to TACF, which began looking at inserting a restoration colony of chestnuts into the forest ecosystem. McCarthy is now the chairman of TACF’s board of directors.

“What’s intriguing about the chestnut is that it’s as stubborn as its mortal enemy,” Rist said. “The fungus kills the tree, but it doesn’t kill the roots. So, when a chestnut tree succumbs and eventually falls, stump shoots or root shoots spring forth to begin the life-and-death cycle all over again.”

The crossbreeding strategy is designed to add just enough genetic material from the Asian chestnut to give the overall tree a viable defense. Asian chestnuts are attacked by the fungus too, but the species has built up enough immunity that it isn’t fatal.

This effort began two years ago, when dozens of ODNR employees and volunteers from the Mohican Trails Club planted 400 chestnut seedlings at the Mohican State Forest in Richland County near Mansfield. Hundreds of other chestnut hybrid seedlings were planted in southern Ohio at the Scioto Trail State Forest in Ross County, and at the Waterloo Wildlife Area in Athens County.

Researchers and volunteers say that the blight will show up again in five to 10 years, adding that it will be 20 to 30 years before state foresters will know how well the hybrid chestnuts have survived.

Chestnut facts

· The USDA counts 919 farms producing chestnuts on 2,500 acres. The top five states with the most chestnut acreage area California, Florida, Michigan, Oregon and Virginia. U.S. chestnut production is less than 1 percent of total world production. Consumption could support 20,000 acres of chestnuts.

· The United States is the only country in the world that can grow chestnuts that does not have a large commercial chestnut industry.

· The United States imports $20 million of chestnuts yearly.

· U.S. consumption is less than 1 ounce per person per year, but 1 pound per capita in Europe and 2 pounds in Asia.

· By its 10th year of growth, the chestnut tree can produce 10-20 pounds of nuts per tree. At maturity (15-20 years) a chestnut tree can produce 50-100 pounds of nuts annually.

· Retail prices for chestnuts range from $3-$10 per pound, which is a superior return to pecans, hazelnuts and other tree crops.