A Chestnut Solution
An American Chestnut in Full Regalia
Herb Darling called and I could tell from his voice that he was excited. "We've made it," he exclaimed. "We've got a resistant strain."
That may not mean anything to many of you, but to those of us who are concerned about our nation's trees, Herb's comment represents perhaps the most important breakthrough in the history of our silviculture.
Herb was talking about the development of a blight-resistant strain of American chestnut tree. And no wonder he was excited. For over twenty years scientists at the New York State College of Environmental Science and Forestry in Syracuse have been working on this problem and now, by splicing just two genes - a wheat gene and a marker gene - with those of the chestnut, they have solved it.
"Our goal was to develop an American chestnut tree that has blight resistance equal to that of a Chinese chestnut and we are there. We've done it," said Dr. William Powell, an ESF professor who leads the research project along with Dr. Chuck Maynard. "The leaf assays show it, the small-stem assays show it," Powell said, referring to the analytical processes the researchers go through to determine the level of blight resistance. "These American chestnut trees are blight resistant."
Although the ESF press release doesn't mention it, this research was initiated by the New York State branch of the American Chestnut Foundation with Herb Darling and Stan and Arlene Wirsig playing central roles and with the Buffalo Museum of Science supporting their efforts. Their initial contact with Maynard and Powell took place in early 1991.
To see what a big deal all this is, let me take you back another hundred years. At that time there were an estimated three billion American chestnut trees in North America. They made up over a quarter of the trees through the Appalachian Mountains and here on the Niagara Frontier. It is only a slight exaggeration to claim that a squirrel could travel from Vermont to Alabama through the chestnut canopy without touching ground.
This is a wonderful, fast-growing tree. Its valuable lumber serves for, among other things: furniture, musical instruments and caskets. It is resistant to rot and there remain chestnut split-rail fences today that were set out in the early 20th century. The mast the trees produce are those tasteful "chestnuts roasted by an open fire" of The Christmas Song. Those nuts also serve as a prime wildlife food.
Add to that their appearance. They grew to 60 to 100 feet in height. In spring and early summer this was one of our most beautiful trees. Their many flowers gave the trees a overall creamy white aspect.
On a rain-swept day in 1992 I joined Herb Darling at the 80-foot construction scaffolding that he had erected next to a chestnut on his property in Zoar Valley. We clamped on restraining lines and climbed up parallel to the tree's several-feet-diameter trunk until we reached the top platform. There I found myself surrounded by those lovely flowers. The only thing that took away from that delightful experience was the fact that we had to climb back down that slippery ladder with lightning flashing nearby.
Just two years later that tree was dead. Like almost all of those billions of chestnuts it died of the blight that was brought to this country by an imported Chinese variety. The foreign trees carried the fungus but were not affected by it. New American chestnuts continue to sprout but eventually they all succumb to the disease.
The national American Chestnut Foundation responded to the loss of this tree by initiating a program of cross-breeding American and Chinese chestnuts but Darling and the Wirsigs proposed a genetic response. This was rejected by the board of the national organization, even when Herb was its president, but the state chapter was permitted to go forward.
Frankly, I became discouraged as time passed and the ESF annual projection was always "we're making progress but it will be just a few more years." Thankfully the genetic solution has finally arrived while cross-breeding continues to have a way to go.
Unfortunately, it is important to note that we cannot yet ask for these blight-resistant trees. The new cultivars must go through a period of testing in federal labs that may take as long as five years.-- Gerry Rising