Beech trees take over northeastern U.S. and it's not a good thing

Posted Feb 26, 2018 by Karen Graham
The increased temperatures and precipitation brought about by climate change have made it possible for beech trees to thrive in the northeastern U.S. and Southern Canada, and researchers say this is not a good thing.
Cankered stem of a beech tree following attack by beech scale and infection by Neonectria (beech bar...
Cankered stem of a beech tree following attack by beech scale and infection by Neonectria (beech bark disease complex) in Ontario
Forest Invasives Canada/Linda Haugen, USDA Forest Service
Climate change is creating a lot of new problems for the environment, and all of these problems will ultimately impact on humanity, including economic losses, health risks and more.
A 30-year study revealed that the American beech, (Fagus grandifolia), a large tree often used for firewood, is dominating the woodlands. The tree has smooth steel-gray bark, glossy leaves, and fine-grained timber but is considered inferior, and of less commercial value compared with other species of birch and maple trees used for making furniture and flooring.
Foliage of the American beech (Fagus grandifolia)  a species susceptible to beech bark disease infec...
Foliage of the American beech (Fagus grandifolia), a species susceptible to beech bark disease infection.
Forest Invasives Canada/Rob Routledge, Sault College,
The study on beech tree dominance
In the study published in the Journal of Applied Ecology, scientists from the University of Maine and Indiana’s Purdue University, led by Aaron Weiskittel from the U of M, have raised concern over forests dominated by beech trees.
In a first-of-its-kind study, the researchers, using data provided by the U.S. Forestry Service, looked at the broad changes that have occurred over a period of thirty years, from 1983 to 2014, in the states of New Hampshire, New York, and Vermont
While the researchers found that the beech tree had increased in abundance in the three states, at the same time, red maple, sugar maple and birch decreased. Interestingly, they found the beech tree had become the dominant tree species in key tourist areas that include the Green Mountains of Vermont, the White Mountains of New Hampshire, and the Adirondack Mountains of New York.
Map depicting the spread of beech scale  Cryptococcus fagisuga  from its introduction until 2015.  C...
Map depicting the spread of beech scale, Cryptococcus fagisuga, from its introduction until 2015. Cross hatching indicates the reported range of Neonetria spp.
Forest Invasives Canada
“There’s no easy answer to this one. It has a lot of people scratching their heads,” Weiskittel said, according to ZME Science. “Future conditions seem to be favoring the beech, and managers are going to have to find a good solution to fix it.”
This is not good news, say the researchers
The obvious effect of beech trees being dominant in forests is their lower commercial value. They will have a negative effect on commercial logging operations and the lumber industry. This reason alone could affect the economic outlook for many communities that depend on the industry.
But there is even a bigger threat to consider - beech bark disease. Beech bark disease is a disease that causes mortality and defects in beech trees in the eastern United States, southern Canada, and Europe. In North America, it occurs after extensive bark invasion by the beech scale insect, Cryptococcus fagisuga.
Beech bark disease weakens host trees  and makes them susceptible to  beech snap   where the trunk o...
Beech bark disease weakens host trees, and makes them susceptible to "beech snap", where the trunk of a beech tree breaks. This is a safety hazard to humans, and contributes to ecological changes in the forest.
Forest Invasives Canada/Joseph O'Brien, USDA Forest Service
While scientists don't yet know the exact mechanism, extensive feeding by the insect causes two different fungi - Neonectria faginata, and Neonectria ditissima to produce annual cankers on the tree. The cankers eventually girdle the tree, resulting in canopy death.
The first case of beech bark disease in the U.S. was reported in Massachusetts in 1929. By 2004, the disease had spread as far west as Michigan and as far south as western North Carolina. The first outbreak of beech bark disease in North America appeared in American Beech (Fagus grandifolia) in Nova Scotia, Canada around 1920.
About 50 to 58 percent of beech trees with the disease die within 10 years of infestation. Older trees, particularly those that are decayed, are also at risk of the disease, Weiskittel said. He says that beech trees’ range will likely expand even more because they’re not appealing to deer, which munch on the seedlings of other species of trees.
“Climate-associated changes in forest composition have been widely reported, particularly where changes in abiotic conditions have resulted in high mortality of sensitive species and have disproportionately favored certain species better adapted to these newer conditions.” the authors concluded.