In Search of Old-Growth

Every time our son Dave suggests a field trip in search of old-growth forests, I get nervous. I also grab my walking stick. That’s because these rumored old-growth remnants are always on steep rocky slopes that discouraged loggers back in the late 1800s. They also discourage me. Navigating up boulder-strewn mountainsides is not my strong suit.

Dave first tested my mettle back in late February of 2002. He had been intrigued by a research paper entitled “Relating Land-use History and Climate to the Dendroecology of a 326-year-old Quercus prinus Talus Slope Forest,” by Charles M. Ruffner and Marc D. Abrams of Penn State University. It wasn’t so much the subject matter that caught his attention but the location of the forest–on the top of Thickhead Mountain above the Detweiler Run Natural Area in Rothrock State Forest. The 463-acre old-growth hemlock/white pine forest in the natural area is one of our favorite places in Pennsylvania. Yet somewhere high above it grows a 65-acre old-growth chestnut oak forest. We had to see it!

Accompanying the article was a rough map of the area. Dave and my husband Bruce studied that map, cracked out the corresponding topographical map, and carefully plotted our route via gravel roads to the closest access point. The winter of 2002 had been snow-free, and we knew that the forest roads would be open so off we went one sunny day.

We left our car by the side of the road and bushwacked through the woods near the rocky mountaintop that rapidly became a talus slope. After carefully picking my way over and around rocks for a half-mile and slowing down the men, I told them to go ahead. I would sit on a rock and wait for them. They weren’t gone for more than a few minutes before the talus slope erupted with chasing, courting chipmunks, providing great entertainment for me during my long wait.

After an hour the sun disappeared and the day turned gray and damp. I put on a second jacket and pulled up the hood. Canada geese honked in the distance and, as the sky darkened, a pair of great horned owls hooted. A couple raindrops pinged down. Then more raindrops fell. Still there was no sign of the men.

I looked around for shelter and spied a white pine tree that appeared to be denser than the others. Just as I headed toward it, I heard Bruce calling to me. They never had found the old-growth. As cold rain pelted down, we made our slow way back to the car, getting thoroughly soaked in the process.

Since we hadn’t actually found the site, I took solace in reading the description of it in the Ruffner/Abrams paper. The “extreme talus conditions of the site [had] prevented exploitation of the timber resources” by charcoal and logging operations. Fairly well-distributed old growth chestnut oak trees dominate the overstory while black birch, red maple, and black gum represent understory trees. “The stand,” they write, “is characterized by low-branching, twisted, sparse-crowned individuals typical of old-growth forests.”Of course, old-growth oak forests on poor sites, such as dry talus slopes, don’t look like old-growth on well-watered and fertile sites. “More important than size,” says eastern old-growth guru Robert Leverett in an Orion article by Tom Horton, “are [the trees’] tops, broken and contorted, flattened in broccoli shapes, craggy limbs devoid of the fine, twiggy branching of younger trees.” Leverett also looks for thick moss growing several feet up a tree because he says that it takes moss centuries to grow half an inch thick.

Such a description was in our minds when we set out on our next search for old-growth forest last November. Ecologist Beth Brokaw, working on the Huntingdon County Natural Heritage Inventory for the Western Pennsylvania Conservancy, had discovered old-growth characteristics in another portion of Rothrock State Forest, what she called the Seven Stars Biodiversity Area. That was only 20 miles from our home and on a brilliant autumn day we went off again in search of old-growth. This time we had more precise directions, we thought.

We took a road that climbed up the side of Tussey Mountain from Colerain and afforded lovely views of the valley below. After several miles of gravel road, we reached the Seven Stars BDA. Dave had been eyeballing the trees above the road on a steep slope strewn with large boulders. Many large chestnut oaks had contorted shapes and broccoli tops. A few of the largest trees had thick moss several feet up their trunks. To me it looked like a troll’s forest and unlike any forest I had seen in Pennsylvania.

“It won’t bring in the ecotourists,” Dave said.

Once again, though, we had looked in the wrong place. It was the forest below the road that most interested Brokaw. That forest had fewer boulders and was more diverse with a fair number of large tulip trees, cucumber magnolias, black gums, and chestnut, red, and white oaks. It also had several charcoal flats and the remains of an old charcoal haul road. Tom Thwaites, author of Fifty Hikes in Central Pennsylvania, maintained that both the flats and the road were evidence that trees had been cut to fuel the Colerain Forges from 1805 to 1850. Could trees not much over 150 years in age be old-growth, Thwaites asked?

“Second growth can be considered old-growth,” Dave said, “depending on how you define ‘old.’ The minimum definition used by Marc Abrams calls for simply a majority of canopy-height trees over 150 years old. But the more standard definition of an old-growth stand is that the median age of canopy height trees of any given species should be half the normal expected lifetime of that species.” Since the life span of chestnut oak trees is 200 to 300 years old, 150-year-old chestnut oak trees could be considered old-growth.

Brokaw, on a field trip she led to the area late in November, told us that she had talked to a forester from Rothrock who had mentioned that there might be pockets of old-growth chestnut oak in the area, but that most of the forest was maturing second growth. If left alone, it would attain old-growth status in not too many more years.But who would decide when it had crossed the line? Leverett contends, in an article he wrote called “Old-Growth Forests of the Northeast,” that “…there is never a point when a forest becomes clearly identifiable as old-growth… [because] forests do not progress toward the old-growth phase via a single path.” He and other old-growth researchers are finding that different kinds of eastern forest age in different ways. For instance, old-growth oak and hickory forests are probably impacted by wind and fire disturbance and may not have thick organic soil layers like old-growth conifer forests.

Then, too, many anthropogenic changes have been wrought on the eastern forests. Original Appalachian oak sites, such as the Ruffner/Abrams research plot, were also dominated by American chestnuts and were called, by earlier researchers, oak-chestnut forests. Today the chestnut component is gone.

Size is also not a reliable indicator. Big trees are not necessarily old trees as we found out on still another old-growth expedition. This time we decided to visit an old-growth site in a state forest natural area, one that I had been told years ago was difficult to reach via a steep powerline right-of-way and not terribly worthwhile. On the other hand, Chuck Fergus, in his excellent and recently-published book Natural Pennsylvania: Exploring the State Forest Natural Areas, had given alternate, more accessible directions to the Mt. Logan Natural Area in Bald Eagle State Forest. Dave was keen to see the place, and I must admit that I hadn’t read Fergus’s account of the site as carefully as I might have. Luckily, though, I did remember my walking stick and Bruce’s.

After a bumpy ride to the end of Nittany Ridge Road, we parked the car and followed a deeply-rutted, mud and water-filled old road, passing two ephemeral ponds on the right. Just before we reached the blue-blazed Winchester Trail, I spotted a porcupine walking along a parallel white pine branch above the road. Then, as we started up the trail, a noise to my right alerted me to another porcupine, high in a large oak tree, peering down at us. Already, this seemed like a great place.

At first the trail was easy. I admired the white pine regeneration in the forest even as the mountain slope steepened and more and more rocks appeared. Ever upward the trail went to over 2100 feet. It wasn’t the ascent so much as the rocks themselves that slowed me down. How would I ever get down in one piece? Still, I persevered.

When we reached the base of the crest, I was almost defeated. Layers of Tuscarora quartzite formed a hogback 20-feet-high and there was no way around it. The blue blazes snaked back and forth up the rocks. Dave had long ago reached the crest. Comfortably seated on the rocky top, his back against a white pine, he egged us on. My walking stick was no help at all. I had to use my hands to pull myself up, and I was a quivering mass of nerves by the time I reached the top. That was when I looked at Fergus’s account more carefully. “The rock [Tuscarora quartzite] is a pale tan, almost white, and on top of Mt. Logan it stands in low cliffs ten to twenty feet in height. Below the cliffs lie boulder fields, also known as talus slopes: jumbled, tilted, clack-together slabs ranging in size from dictionaries to pool tables.” Exactly.We sat on the crest to eat our bag lunches as turkey vultures floated past and we enjoyed a view of blue mountains through the trees. The forest had been silent on our way up the trail, but once we reached the summit we could faintly hear the traffic from U.S. 220’s four-lane, limited express highway to Lock Haven below us.

Somewhere below us also was the old-growth hemlock forest. I groaned when I saw that it too was strewn with boulders. I not only struggled over rocks but through almost impenetrable thickets of mountain laurel. I made it to the edge of the old-growth, and once more found a rock while the men continued on. Still, I did see the difference between the surrounding second-growth oak and the old-growth hemlock. Thick, thick layers of moss covered the leaf and needle duff on and between the rocks. Long ago fallen large trees were hoary with moss and the live trees had the reddish-brown bark of old-growth hemlock.

Bruce soon joined me as Dave went farther afield to explore the 50-acre site. As we sat under the swaying hemlocks waiting for him, a common raven croaked past. Then we heard the clear “fee-bee” of black-capped chickadees and three surrounded us and scolded “dee-dee-dee.” No doubt humans were a novelty to them in this remote place. We saw no sign of deer. Surely no self-respecting deer would risk their graceful, thin legs in such a pile of rocks. A coyote would, though, and we found a pile of very fresh coyote scat.

“This is what I wanted to see,” Dave said when he returned. “This is what our mountain probably once looked like.”

How I got back down the mountain is probably better left unsaid. I did make it on my own after I inched my way off the crest with Bruce’s assistance. Otherwise, I blessed my walking stick many times and made a vow (as I have on other trips) that if I made it safely back, I would never again climb a steep, rocky trail.

On the other hand, seeing more “old-growth” is a mighty motivator. “Time travel,” Dave calls it.