The rewilded orchards at Lesesne might seem commonplace to an uninformed trekker. But if you know their backstory and telling characteristics, strolling through one of these groves feels like a real-life miracle.

“When the European colonists got here, American chestnut trees were a dominant species throughout most of the eastern piedmont and Appalachian Mountain range,’’ says veteran forester and TACF board member, John Scrivani, 72. Their trunks could grow to be 10 feet wide and stretch upward of 105 feet into the canopy; limbs spanned an equally wide footprint. The trees could live for three or more centuries and covered an estimated 300,000 square miles of land from Maine to Mississippi.

“This was the tree of early America,” writes author Susan Freinkel in her book, American Chestnut: The Life, Death, and Rebirth of a Perfect Tree. Carpenters prized their strong, straight-grained, and decay-resistant wood. Farmers praised their ability to feed and produce world-class livestock. Sportsmen revered them as a primary food source for wildlife. Gourmands celebrated their dry fruit as the world’s tastiest variety of chestnut.

Then came a virulent, invasive fungus from east Asia called Cryphonectria parasitica. Better known as chestnut blight, it was accidentally introduced in New York by way of imported Japanese varieties in the late 19th century and spread like wildfire through eastern forests.

“The fungus enters a tree through a wound in the bark, spreads laterally around stems and limbs, destroying the vascular system and killing growth above the point of infection,” says Scrivani. “The tree eventually dies back to the ground and, while new sprouts often emerge, they rarely grow large enough to flower. Reproduction and natural evolution halt.”

By 1941, the blight had eradicated 3.5 billion American chestnut trees and rendered the species functionally extinct.

While most 1940s biologists forecasted permanent doom for the American chestnut, some clung to a wily optimism. […] A loose cadre of agronomists, foresters, biologists, university researchers, and interested citizens took shape. Some studied the blight fungus and looked for clues to how it could be stopped. Others scoured forests for nuts and surviving trees, or gleaned clippings from sapling sprouts that they grafted onto Chinese rootstock for study.