U.S. Forest Service hopeful chestnut tree will spread again

It’s time for a return of the American chestnut… but not an All-American chestnut.

In the early 1900s, the chestnut blight was introduced to the United States and, over 50 years, an overwhelming majority of the billions of American chestnut trees were wiped out.

On Wednesday, five chestnuts were planted as educational trees at the Marienville Ranger District office of the Allegheny National Forest.

“Five small seedlings, the promise of a future yet to be, mark the return of the American chestnut to the Allegheny plateau,” Forester Scott Tepke said. “The five seedlings planted here at the Marienville Ranger District office will provide the ANF with a great opportunity to introduce our forest restoration effort.”

An interpretive sign will be put up near one of the seedlings to inform visitors of the effort.

“These are the first of many potentially blight-resistant seedlings that will be planted in partnership with The American Chestnut Foundation (TACF) to test the performance of the trees in a natural environment and restore them to their natural range.”

“The American chestnut tree reigned over 200 million acres of eastern woodlands from Maine to Florida, and from the Piedmont west to the Ohio Valley,” Tepke said. “It is a fast-growing, rot-resistant tree that was essential to the lumber industry and produced a reliable crop of nuts for wildlife and humans.”

“An estimated 4 billion American chestnut trees, one-fourth of the hardwood tree population, grew within this range,” he said. “In Pennsylvania, the density was even higher. Some counties had 40 to 50 percent of their forested acreage in American chestnut until the first half of the 20th century, when they succumbed to the chestnut blight, a lethal fungus infection.”

Tepke said the percentage of the Allegheny plateau made up by American chestnuts was up to 15 percent.

“The loss of the American chestnut left a huge gap in our forest ecosystem,” he said.

The trees were valuable to animals and humans. “It was referred to as ‘the cradle to the grave tree’ since it was used in all aspects of life,” Tepke said. “The tree produced large, consistent crops of sweet nutritious nuts that supported a wide variety of wildlife – chipmunks to black bears – and used to feed livestock as well as people. The wood is strong and highly decay resistant; it was valuable for construction, easily worked for furniture making, and has good sound qualities for making musical instruments.”

“Planting chestnuts forwards the goal of the U.S. Forest Service to maintain species diversity within a forest,” he said. “The hope is that the ANF will play an important role in testing, evaluating, and adding to the knowledge base of the American chestnuts. This tree played such an important role in the forest ecosystem and in society that it deserves to regain its rightful place.”

“My first expectation is that this project might meet with some controversy, but through education and understanding, the ANF will become home to the new American chestnut,” he said. “It is my desire to stir enough public interest so that the ANF and public volunteers can join together in this effort.”

To bring back American chestnuts, scientists are introducing some genetic information from Chinese chestnuts that have proven resistant to blight. “The seedlings produced by TACF are 94 percent American chestnut,” Tepke said. “The development of resistance within American chestnut would have occurred naturally but would have most likely taken thousands of years. We humans are just speeding up the process.”

“A promising procedure called backcross breeding was started in the 1980s by The American Chestnut Foundation to breed blight-resistant American chestnut trees,” Tepke said. “After years of breeding and testing in plantations, American chestnut seedlings are now ready to be tested as part of the natural ecosystem.”

“Through the breeding process of backcrossing and tree selection, the only change to these seedlings is the introduction of the blight resistance characteristic,” he said. “The resistance is thought to be found in a combination of genes within the trees’ genetic makeup. Genetic mapping research is ongoing at this time for all of the chestnuts to try to better understand how blight resistance takes place.”

The five trees planted on Wednesday are a practice group. There are many more to come.

“Next year, the ANF will plant seedlings and nuts to test several different genetic families in the northern part of the chestnuts’ natural range,” Tepke said. “Planting will continue over several years as seedlings are limited. In the coming years, thousands of American chestnut trees will be planted on the Allegheny National Forest in order to test the tree’s blight-resistance, cold hardiness, and ability to compete with other forest trees.”

Tepke and ANF Global Information Systems Specialist Veronica Lopez created a system to locate the ANF’s most suitable sites for chestnut restoration.

The effort has earned awards along the way. The Forest Service gave it an Eastern Region Honor Award for Revolutionizing Effectiveness and Efficiency.