Silvicultural Strategies for Restoring American Chestnut

Dr. Julia Burton, Assistant Professor in the Department of Sustainable Resources Management, is researching how forest management strategies can be used to help restore American chestnut trees.

American chestnut trees historically dominated eastern forests, growing to such large sizes that they were sometimes referred to as the sequoias of the East Coast. With rot-resistant wood and nuts that were a wildlife and livestock food source, American chestnuts played an important role in both the forest ecosystem and local communities until the early 1900s when chestnut blight was introduced to North American forests. Chestnut blight (Cryphonectria parasitica) is a pathogenic fungus that effectively wiped out American chestnuts from eastern forests.

A transgenic American chestnut seedling.

Dr. Burton’s research addresses how to introduce the transgenic chestnut seedlings that Dr. William Powell and his team at ESF have developed into existing forests as part of a larger landscape restoration strategy. Dr. Powell, a professor in the Department of Environmental Biology, has developed transgenic American chestnut varieties that are resistant to chestnut blight. In 2019, Dr. Powell received a $3.2 million grant from the Templeton Foundation to support American chestnut restoration. Transgenic American chestnut seedlings are currently expensive to produce, which means there are high stakes when transplanting them into the forest ecosystem. Since the tree has been absent from the forest for so long, little is known about its life history, growth patterns, and behavior. Dr. Burton is exploring how to manipulate environmental conditions in forest ecosystems to promote the growth and survival of American chestnut seedlings.

With SUNY ESF’s Forest Properties staff, Dr. Burton has implemented a harvesting approach called a shelterwood, which is commonly used to promote oak regeneration in eastern forests. American chestnuts are expected to have similar environmental requirements as oaks. Shelterwood harvests leave older and larger trees to release seeds and provide shade while also reducing temperature extremes and controlling competing vegetation. Using shelterwood treatments with a range of densities of trees left standing, Dr. Burton is assessing how light and resource availability affect the early growth and survival of American chestnut seedlings in collaboration with graduate student Garrett Evans and SRM faculty colleague and tree physiologist Dr. John Drake.

One of Dr. Burton’s research sites.

Visit the Forest Ecosystem Management and Silviculture Lab at ESF to learn about more ongoing research in silviculture. Visit the American Chestnut Research & Restoration Project at ESF to learn more about ongoing chestnut research.  

Watch the video to hear more from Dr. Burton about her research on American chestnut and see examples of the shelterwood treatments.