The American Chestnut

The American chestnut (Castanea dentata) was once the most common and commercially valuable tree in the eastern United States. It ranged from central Maine to southern Appalachia. Legend has it that when settlers first arrived to the new world a gray squirrel could have run from Georgia to Maine without ever touching the ground. It would have done it along the branches of American chestnut trees. These massive trees dropped thousands of pounds of delicious and energy rich chestnuts per acre every year. This is unlike the oaks who generally drop large bitter tasting acorns on a semiannual basis. Their reliability and enjoyable flavor made chestnuts an important food for all wildlife from squirrels to deer and black bears. Humans also relied heavily on this natural food source which was harvested by the ton from the eastern forest every year. They were used to fatten livestock as well as feed families. Holiday songs were even written including this iconic food source being roasted on an open fire. This all changed around the turn of the century when an exotic fungus, known commonly as chestnut blight, was introduced to New York City. By 1930, nearly all American chestnut trees had been wiped from the landscape. Today, the American chestnut is considered "functionally extinct". While the towering specimens our ancestors walked beneath have all vanished, their root systems are still alive within the ground. The blight only kills the living plant above the ground. These last remaining specimens continue to send up new growth, some of which live for up to 10-15 years before finally succumbing to the blight.

The American Chestnut Foundation is a national organization dedicated to the restoration of our eastern chestnut forests. They have been working for decades crossing American chestnut trees with Asian chestnuts that are naturally blight resistant. The goal is to eventually breed a tree that is nearly pure American chestnut but retain the blight resistant genetics of their cousins from Asia. There are signs that they have accomplished this goal but it will be years before a large supply of these trees are ready for the market and mass plantings in our forests. I joined the ACF with my Trees and the Maine Forest class to support this worthy cause and get a really snazzy window sticker. An added bonus to new membership was ten chestnuts harvested from the few productive trees remaining in the state of Maine. We planted them a few weeks ago and have had four come up thus far. Before laying eyes on these seedlings, I had only ever seen one American chestnut tree as a child. Needless to say it was pretty exciting to witness the beginning of what we dream could someday be a towering chestnut tree in the T.A. Forest. While the nuts we received are not thought to be blight resistant, I was still hopeful that we could have some success growing them on T.A. grounds as the ACF does not list any known chestnut trees anywhere in the town of Saco. A ten mile gap between the nearest infected tree is generally good enough to allow a chestnut tree to reach an age old enough to begin producing nuts.

An American chestnut seedling growing in my classroom at T.A. (Photo by Julie Vail)

Today, while working with one of my tree classes in the T.A. Forest, I could not believe my eyes when I took a closer look at a clump of saplings sprouting up ten or so yards form the Eastern Trail. Right there in front of me was a wild American chestnut! I stood quietly trying to talk myself out of what I really wanted it to be while my students conducted their lab work all around me. The more I observed the tree, the more confident I became in what I had found. Finally, I shouted to get everyone closer and we all shared in the excitement of our new discovery. This specimen is just leafing out but the leaves already show the prominently toothed margins and long narrow shape indicative of this species. One of the most confirming features of this specimen is the dead standing tree growing from the middle of the clump of saplings. This is classic for a tree that struggles to grow above ground for more than a decade before being snuffed out by blight. I can't help but wonder how old the root system of this tree is and what the original specimen must have looked like. It is growing beneath some 70' tall eastern white pines (Pinus strobus) that most likely sprouted around the time Thornton Academy was in its infancy during the 1800s. At that time American Chestnuts would have been one of the most common deciduous trees in the area.

New American chestnut leaves in the T.A. Forest (Photo by Julie Vail)

Note the standing dead tree at the center of the clump of saplings. This individual was most likely killed by blight after several years of growth. The small trunk to its left has leaves on the upper half but the lower branches look to be infected.  (Photo by Julie Vail)

While the excitement of finding a wild chestnut growing in our forest has still not worn off, there is a slightly somber feeling as well. Having an infected tree in our area means that there is also blight in our area and our new seedlings are almost certainly doomed. All we can do is hope that our trees can make it long enough to act as ambassadors of an embattled but resilient species. In the mean time, we will allow the leaves on our wild specimen to mature before harvesting them and sending them off to the American Chestnut Foundation to confirm our identification an possibly list the only known American chestnut in Saco.

Touching an American chestnut is like reaching back into another era. It is hard not to wonder what our eastern woodlands would look like today had the blight never been introduced to North America. (Photo by Julie Vail)

Special thanks to Trees and the Maine Forest senior student, Julie Vail, for her amazing photography for today's post.