Although the old adage “money does not grow on trees” may be true, this does not stop scientists and activists alike from their efforts to revive the once-prosperous facet of American cuisine: the chestnut. Collections of inspired environmentalists from The American Chestnut Foundation (TACF), in addition to a variety of groups throughout the country on social media, are embarking upon a project to reintroduce the American chestnut tree (Castanea dentata) to its former forest ecosystems. This campaign, while growing in popularity, will require not only eager planters, but an understanding of the near-collapse of the American chestnut tree population, the science behind agroforestry, and how new genetic modifications can bring back those beloved nuts roasting on an open fire.
Measuring several feet in diameter and capable of growing between eighty to one-hundred feet tall, the American chestnut tree that once dominated the Eastern United States in numbers in the billions, fell victim to the chestnut blight (Cryphonectria parasitica), a disease-carrying fungi, early in the twentieth century. The wood of the American chestnut tree was rot-resistant and straight-grained, therefore it was a valuable building material for furniture, fencing and the construction of log cabins during colonial America. Until the chestnut blight decimated nearly all of the trees from the landscape of the United States, the chestnut also served as an important contributor to the American rural economy.
Chestnuts provided a nutritious snack for livestock, such as pigs and cattle, and people, since four ounces of cooked chestnuts contain approximately 150 calories, six grams of fiber, and thirty-two grams of carbohydrates, according to a newsletter from The American Chestnut Foundation. Despite the devastating impact of the chestnut blight, the American chestnut trees are only considered to be “functionally extinct” because the fungus is unable to kill the tree’s underground root network. Sprouts emerging from hundred-year-old stumps give tree-lovers hope, but without comprehensive research and careful planning, the sprouts will not be able to grow far.
University of New England professor of Environmental Studies Thomas Klak, Ph.D., is working with his students to restore the American chestnut tree to forest ecosystems after a team of scientists figured out the secret behind saving them all. Through the insertion of a wheat gene into seedlings, a method used in a variety of food plants, such as bananas and strawberries, the chestnut seedlings are protected against the fungal blight. Similar approaches have been devised beginning in 1990 by the New York Chapter of The American Chestnut Foundation (NY-TACF) and the State University of New York’s College of Environmental Science and Forestry (ESF). The wheat gene discovered to be effective in both experiments is known as oxalate oxidase, or OxO. According to TACF, this enzyme “breaks down oxalic acid, which is one of the primary ‘weapons’ the blight fungus uses to attack chestnut trees”.
Additionally, researchers at ESF have confirmed that the inserted OxO gene does not have any harmful ecological impacts or negative human health repercussions. Once federal agencies like the Environmental Protection Agency (EPA) and the U.S. Food and Drug Administration (FDA) complete their environmental and health evaluations of genetically-engineered American chestnut trees, these trees can be widely distributed and planted. Producing trees protected from blight has also been achieved by breeding the American chestnut with the blight-resistant Chinese chestnut, providing another alternative of effective genetic modification that could restore the American chestnut populations. However, breeding with another species of tree comes with its risks. According to an article from the Washington Post, the blight resistance in Chinese chestnuts are “controlled by several genes” and that “inheritance by future generations of chestnuts is consistent,” therefore this breeding process could probably require multiple generations before achieving any degree of blight resistance (Washington Post, 2018).
There have been some arguments on how scientists should proceed with cultivating the blight-resistant American chestnuts. In an article for WBUR, Michael Novack, one of the founders of the Massachusetts chapter of TACF, states his concern for genetically-altering tree species, despite it being a more fast-paced process. Given the success of conventional breeding, Novack claims that “we are on very shaky ground if we think we can engineer ecosystems,” and that there “is no environmental imperative to rush to do this using genetic modification” (WBUR, 2018). Additional worries about the GMO project pertain to its connection with Monsanto, although Dr. Powell, a professor at the SUNY College of Environmental Science and Forestry, denies that Monsanto has direct ties to the chestnut restoration project, regardless of the fact that Monsanto gives money to the New York chapter of TACF. Controversy has surrounded Monsanto since 1996 when the multinational agricultural biotechnology corporation first developed their weed-resistant, genetically-modified (GM) RoundUp Ready seeds. Skepticism still remains in today’s agricultural community from those who fear the long-term health and environmental impacts of genetically-altered crops.
Whether admired or feared, genetic engineering of the American chestnut “would be the first-ever genetically-modified plant used to help save a species and a great public relations success story for GMOs in general” (WBUR, 2018). The future of the American chestnut tree may not lie solely on genetic alteration, yet it may be the price to pay for a nation to once more reap the benefits of the cherished Castanea dentata.
n.a. “Background on American Chestnut and Chestnut Blight.” SUNY College of Environmental Science and Forestry, n.d. https://www.esf.edu/chestnut/background.htm. Accessed 29 Feb. 2020.
n.a. “History of the American Chestnut.” The American Chestnut Foundation, n.d. https://www.acf.org/the-american-chestnut/history-american-chestnut/. Accessed 29 Feb. 2020.
Newhouse, Andrew. “We nearly killed off these trees. But biotech can bring them back.” The Washington Post, 29 May 2018, https://www.washingtonpost.com/news/theworldpost/wp/2018/05/29/biotech/?outputType=amp. Accessed 6 Mar. 2020.
Swartz, Josh. “The ‘Most Ambitious’ Species Restoration Project in the World.”WBUR, 28 Dec. 2018, https://www.wbur.org/endlessthread/2018/12/28/that-old-chestnut-encore. Accessed 1 Mar. 2020.
UNE News. “Thomas Klak’s Project to Restore the American chestnut tree featured on NEWS CENTER Maine’s 207.” University of New England, 12 Dec. 2019, https://www.une.edu/news/2019/thomas-klaks-project-restore-american-chestnut-tree-featured-news-center-maines-207. Accessed 1 Mar. 2020.