Where Have All the Beech Come From?

Posted: February 11, 2014

How did American beech become the predominant component in many forested stands and what should a landowner do about it? Learn more about beech in Pennsylvania's forests.

By Jim Finley, Ibberson Professor of Forest Management, Penn State Dept. of Ecosystem Science and Management

American beech is a tree you can either love or despise – hate might be too harsh a word. While it is not as ubiquitous in the Pennsylvania as red maple, black birch, or black cherry, which are the three most common species before beech; nor is it as common as sugar maple, hemlock, white ash, chestnut oak, northern red oak, or black gum that comprise the rest of the top ten trees in the state.

The most recent US Forest Service assessment of Pennsylvania’s forests completed in 2009 and published in 2012 found an estimated 592.8 million beech trees one inch and larger in diameter (measured 4.5 feet above the ground or “diameter breast height”). There are 1,558 million red maple trees, about three times as many as beech, in the same size classes. Beech occurs across the state, but is most common in the northern counties and locally in the southeastern and southwestern corners. It is relatively uncommon in the ridge and valley areas of the state.

Beech has in the past occupied many economic niches. At one time, it was a species of choice for wooden household items – shoe trees, hangers, bowls, and utensils. Because of its ability to sustain impact, it was a preferred wood for heels in women’s shoes. Its density helped make it an excellent fuelwood. While it does not do well in outdoor applications, after we learned to use creosote and other wood preservatives it was commonly used for railroad ties. Today, though, it is not much favored and that helps to explain part of its apparent resurgence in the state.

Ecologically, hunters often consider beech important. In the northern counties, it is often an important source of mast as it is the only nut producing species in many of these forests. Unfortunately, it is not a very consistent mast producer as good seed years occur every three to seven years. Because its flowers open relatively early, when the leaves are about a third of full size, it is very susceptible to spring frosts. Even in those years, it may appear to produce nuts; however, close inspection will show that many of the burs are empty – the nuts did not form.

While beech does not have consistent seed crops, it does develop well from seeds. Surprisingly, in good seed years quite a few seeds survive wildlife searching to germinate. Many of the “seedlings” seen in beech stands are actually root sprouts. Beech roots are normally rather shallow and they respond to injury and light by sending up sprouts, which can be identified by the fact that they are somewhat clumped near each other. As well, you will see much of the beech reproduction under the crowns of existing trees or around stumps. Research suggests that the larger the parent trees diameter, the more sprouts it produces.

So, why is beech despised by some? Forest owners and managers know that beech is very shade tolerant. That is, it can germinate and grow slowly under relatively high amounts of shade. Some books list it as the most shade tolerant tree in the state. With this characteristic, beech can become established under the forest canopy and languish there for years competing with more desirable species. If light levels are high enough for other species, such oaks, tulip, ash, yellow birch, cucumber, or even red maple, preferential deer browsing gives beech the edge. White-tailed deer apparently rank beech very low in their food choices; while they do use it some, they seem to eat nearly every other tree species first.

Recall beech’s root sprouting ability. Bigger trees produce more sprouts. Because the species has a relatively low economic value, in high grade or select cuts (where there is a tendency to take the best and leave the rest) beech is often left to continue to grow. Sometimes, too, owners want to leave beech in their stands in the hope of attracting wildlife to its mast. Not only do big trees have larger root systems, the stimulus of increased light on the crown might promote more sprouts and seeds. In the gaps created by partial cutting, beech sprouts proliferate because of root damage from logging and the better growing conditions. On a positive note, sometimes these sprouts can and do develop into good stems; however, sometimes they don’t as they die from stress, site conditions, or insects and diseases.

Beech across the northeastern United States has suffered tremendously from the beech bark scale complex. This scale insect in this complex showed up in Nova Scotia in the 1890s. Since then, it has moved across south into Pennsylvania, Ohio, and West Virginia. Once infested with the scale, trees often succumb to one of two nectria fungi that subsequently kill the tree. This complex is particularly hard on the larger trees in a stand. Beyond noticing the small white flocking or cottony masses on the smooth bark of newly infected trees, trees will eventually exhibit patches of collapsed, wrinkly bark and then frequently snap or break 15 to 20 feet off the ground. These now dead trees create gaps and spur on the sprout development and competition.

All of these issues – sprouts, deer, cutting, and beech bark disease complex – increase competition for space and other tree seedlings struggle against beech. Clearly, in some stands, beech seedlings are proliferating. The same US Forest Service study shows that beech is the most common tree seedling (less than an inch in diameter) in Pennsylvania. In the 2012 report, Pennsylvania reportedly hosted 33.7 billion tree seedlings. Of these, 4.45 billion, or 1 in 8 seedlings, was beech. Looking back to the previous report published in 2008, there were 4.2 billion beech seedlings – more than 200 million grew between the two surveys.

If you own or manage a woodlot with a beech component you might be tempted to eliminate beech. It is seldom a not a good idea to completely remove a native species; however, as you work with the forest, think about the role beech plays. Understand that it can and will take advantage of changing conditions and become very competitive. If you harvest trees, assess whether you need to control it before creating better growing conditions. Always, before cutting any stand, assess the regeneration and consider if you have enough diverse seedlings to regenerate the forest. Even if you are just thinning the woods, regeneration and competitors to its success are always a consideration. It is good forestry and stewardship to address the challenges early and before reducing options by harvesting.

To learn more about woodlot management you can check out these publications:

Regenerating Hardwood Forests: Managing Competing Plants, Deer, and Light

Timber Harvesting: An Essential Management Tool