Protecting New Hampshire's Trees: Elm, Ash, and Chestnut

Oct 4, 2017

The fall foliage season is sweeping through New Hampshire, causing residents and leaf-peepers to appreciate anew the forests in the state.  The colors of the season are a function of forest health, and we look closely at efforts to restore and protect three iconic tree species: elm, ash, and chestnut.  And a new report finds that New England is losing 65 acres of forestland per day


GUESTS:

  • Dave Anderson - Director of Education with Forest Society and co-host of NHPR's Something Wild.
  • Jeff Garnas - Assistant Professor of Forest Ecosystem Health in the Dept. of  Natural Resources and the Environment at UNH.
  • Christian Marks -  ecologist with The Nature Conservancy’s Connecticut River Program. He studies floodplain forests and is collaborating with the U.S.D.A. Forest Service to develop American elm selections with greater tolerance to Dutch-elm-disease.

Check out the Fall Foliage Tracker from VisitNH.gov for the best places and times to see the changing leaves. 

Check out the AMC-NH website for tree identifying guides. 

American Elm and Slippery Elm: Trees Decimated By Fungus

The USDA Forest Service has created a website for reporting “survivor elms” if you are interested in reporting an exceptionally large surviving elm tree to researchers.

The proceedings of the American elm restoration workshop 2016 have just been published on-line this week. It was the first workshop to bring together researchers working on restoring the American elm in two decades. The proceedings includes articles of current elm research including on elm pathogens and elm restoration. Marks contributed an article on the ecological role of American elm.

The Forest Service also has a webpage with information on identifying and managing Dutch-elm-disease

An elm's leaves shrivel and turn yellow as a result of Dutch elm disease.
Credit Joseph O'Brien; USDA Forest Service

Dutch elm fungus came to the United States from the Netherlands by way of a shipment of logs in 1930. It is spread by beetles and through the root system, and by 1970, most of the elms in New Hampshire and in the Eastern United States were infected and had to be cut down. 

American elms thrive in floodplains, and help support an extensive ecosystem. 

Read about the project to develop disease-resistant strains of American elm

A Slippery Elm in Quebec
Credit Cephas; Wikimedia

The slippery elm (also called the red elm) is not tolerant to flood plains and is typically found in higher ground, in more acidic soil. It was also decimated by Dutch elm fungus. Now, scientists are propagating more resistant slippery elms from trees that were not destroyed by the fungus in Northern Vermont. 

Read more about the effort to rebuild the slippery elm population

Emerald Ash Borer Threatens Ash Trees In New Hampshire

Emerald Ash Borer
Credit USDA

The Emerald Ash Borer's larvae burrow into the inner bark of ash trees, and are commonly spread to other regions by firewood. Infestations have been found in regions of the Midwest including Indiana, Illinois, and Minnesota, as well as the East Coast, in Virginia, Pennsylvania, and New York. 

Emerald ash borers were detected in ash used for firewood in New Hampshire in 2013. 

Green ash tree killed by Emerald Ash Borer.
Credit Forest Service, USDA

American Chestnut Meets Japanese Chestnut To Create A New, Stronger Tree

Before the chestnut blight in the 1920s, the American chestnut made up around 30 percent of hardwood trees on the East Coast. It was nearly wiped out by a fungus brought to the United States on imported Japanese chestnut trees.

Now, scientists are experimenting with cross-breeding the American chestnut with the Asiatic chestnut, which is blight-resistant, to create new, stronger trees. American chestnuts provide food and shelter for plants and animals, and the wood resists rot, making it a valuable for construction. 

Learn more about the American chestnut at the American Chestnut Foundation

American chestnut leaves and nuts.