American Beech: A sad tale
If you have spent any time in the woods around here, you may have noticed the smooth grey bark of the American Beech.
There are some iconic stands around where there are only these smooth beautiful grey stems on a knoll or a hillside with little in the understory but Canada mayflower. If you have seen one of these stands in your wanderings, you will probably remember it. Sadly, there are fewer and fewer of these stands to see.
Often these stands are so special, they are like shrines within the forest and are left when the woods around them is harvested. Beech has had low timber value, and these stands have high aesthetic appeal. For the past 30 years or more, the beech trees have been under assault. Throughout the Northeast, the population of an insect called beech scale has been on the rise. These tiny bugs feed on the smooth grey bark of the beech tree. Their attack shows up as brown pocks, sometimes with white fuzz. As time goes on, the pocks in the infected tree become more frequent. Eventually, as the disease progresses, the bark becomes rough and breaks up. A secondary infection called “nectria” puts its fungal roots deep into the wood and starts to feed off of the wood and bark. Eventually, the once-smooth tree bark is cracked, platy, and blackened. Limbs start to die and the tree looses vigor. The crown breaks up and the whole tree dies — one here, many trees there. This is happening all over the place. While the tree is dying other fungus and insects attacks the tree. Woodpeckers hollow out cavities in the trees. In some cases, the trees fall down. Often, since it is a great fuel wood, people often go in to their woods and cut the dying trees out.
Beech has another familiar form. When a mixed hardwood or pine forest stand is harvested, beech trees often prolifically take over the harvested area and form a thick wiry mass of twiggy grey saplings. Their survival strategy is based on their ability to grow in the deep shade. They propagate via a beechnut that is prized by bears, deer and squirrels. They shed their nuts in huge quantities in some years and few in others. Big nut crops shed in a year when the soil is roughed up by a timber harvest provide the perfect opportunity for beech to get a foothold on the landscape.
By the way, the nuts are delicious. But there are far too many of them for the animals or a wandering person to eat. When a forest has been thinned out, sometimes all that comes back is beech. It remains to be seen whether these trees can make the leap from wiry understory to majestic grove. But, the form the understory saplings take usually suggests otherwise.
Sad as this story is, New England has great diversity of trees. There are many species of trees in the forest. A deadly pest to one species has no affect on another. There is also genetic diversity with a species. That is where the hope lies, hope that the species will develop resistance in the trees some of the trees that are not infected. Furthermore, some of those terrible beech thickets will one day surprise us and turn into beautiful groves.
Swift Corwin is a member of the Peterborough Conservation Commission.