Cucumber in winter - photo by Ed Frank

Cucumber in June - photo by Carl Harting

For me personally the size of the trees is impressive, but the signs of age exhibited by some of the trees has an even greater impact. One cucumber tree has shaggy bark extending up the tree for at least 50 feet. In the winter we thought is was a cucumber, but its expression was so unusual that we wanted to see the leaves to remove the last vestiges of doubt. We looked at black gum with deeply etched crevices between the bark scales. There was a black walnut again with impressively shaggy bark. Sugar maple kept in style with shaggy bark of its own. There are large beech trees, with smooth gray bark, for the most part unmarked by vandals and without signs of beech bark disease. One large maple had moss growing thirty feet of more up its trunk smoothed by balding. Some of the oaks had furrows in the bark deep enough to fit your hand. There were trees with staghead branching forming the vaulted canopy, There was a dead basswood tree that had fallen across the trail. In the chain-sawed end where the trail had been cleared, Dale counted 178 rings at a height of 19.2 feet above the base of the tree. All the rings were close together, rowing with even finer bands near the outer bark. How long does basswood live? I don't know. Both large oaks and tuliptrees had many examples of thickly furrowed bark on one side and balding to an almost smooth surface on another. The impression was of age - true or false these trees felt old.

Ancient sugar maple with mossy trunk - photo by Carl Harting

Carl Harting and Dale Luthringer examine the mossy sugar maple - photo by Ed Frank

One of the discussions we had was the old debate of whether this was old growth or not. To some degree most of the eastern forests have been impacted by human activities. The question becomes in the east, how much impact can man have had before something can no longer be considered old growth? Maurice Schwartz at one time posted to the discussion list a post listing 98 definitions of old growth he had located on the internet. Was this area old growth? I suppose it depends on your definition and how you interpret the landscape in front of you. A nice discussion of the characteristics of old growth can be found on the 500-year Forest Foundation website - http://www.designgroup.com/500yearforest/growth/index.htm   I am not sure if many of you have visited the website.

Here in the Big Woods area of mcconnells Mill State Park there were no signs of stumps or other logging activities visible. Anthony said there were two stumps visible in the entire area. Dale felt that the area had been selectively logged at some point in the past, but that the signs of the operation had long since faded and the stumps rotted.

On the site we found many species that likely exceeded 150 to 200+ years in age: Cucumbertree, Tuliptree, Sugar Maple, Red Maple, Northern Red Oak, White Oak,, and American Basswood. Dale reported finding an Eastern Hemlock near the mill and some American Beech that also might meet this age criteria. There are some old looking Black Walnut in the park with shaggy bark. Personally I want to add Black Gum and Chestnut Oak, but this is only an impression with no hard support for the estimate. There is a chance that other species besides these may reach similar ages in the park. There is no way to look at a tree and say this tree is exactly this age - an educated guess is made based upon what we know are characteristics of old age.   There was an uneven aged canopy - older fat trees mixed with younger skinnier ones. There were downed logs on the forest floor. Perhaps there were not as many as can be found at places like Cook Forest, and the distribution of the downed logs varied from areas with few to areas with many downed logs. There were occasional standing snags among the trees, but they were few in number. What does this tell you? Are they absent because of human activities or absent because of local conditions?

Pit and mound topography: There are some pits and mounds related to tree falls. I personally am not sure how definitive that characteristic really is. The time duration of the tip-up mounds would be dependant on the type of soil present on the site and the species of trees involved. It is dependant on the speed of erosion and other mass wasting processes on the site.   Areas containing float blocks of large rocks can easily be mistaken for pit and mound topography, especially if covered by a layer of soil or moss.

Other characteristics:   There were some treefall gaps. There seemed to be a diversity of trees and plants, we did not search for amphibians or invertebrates. There were a number of different bird calls and small squirrels and chipmunks present. We saw white-tailed deer. There were signs of other mammals.

One classification system mentioned by Dale involved determining whether or not here were at least 6 to 7 trees 150 years or older per acre. An acre is a circle just under 120 feet, or 40 yards in radius. In this area that was generally a circle about as far as you could easily see through the trees. There were commonly 5 trees per acre that made this age category - if our age estimates were right. There were big tuliptrees scattered everywhere, but were likely not be old enough to meet the 150 year criteria. Is it old-growth? I still don't know. It is a matter of what definitions you use, and what interpretations you make of what you see.

On future trips to the area I would like to measure more of the mid-to-small sized trees of other species I could see growing in the area to better characterized the diversity of trees present on the site. I would like to better document photographically some of the old-age characteristics exhibited by some of these trees. Examples like these are extremely uncommon. I would want to make sure that the GPS location of the trees I photographed were taken. I am convinced that there is a state record beech tree in the area, given the large number in the upper 110's and low 120's. Anthony has looked, and so have Carl and I, without luck, but still...

Ed Frank

Champion Cucumbertree with Anthony for scale - photo by Carl Harting

In contrast with most of the sites down inside the gorge itself, this site
is hardly inaccessible. It's always been a mystery to me why it contains so
many large and tall trees. It is clear where the old property lines were
from the abrupt changes in tree size and the presence of stumps in adjacent
areas. Though I usually referred to it as "old-growth", I have questioned in
previous posts how "virgin" the site is never believing that it was
completely untouched. I've explored about 80-90% of its reputed 75 acres
and have only seen two very old stumps. I've always assumed that the farmer
that settled that land, and the subsequent owners kept that piece as a
timber reserve only taking out a tree here and there over the years as they
needed lumber. I doubt that it was ever clear-cut as there are some trees
that show very old bark patterns and other signs of advanced age.

As Ed reported, Dale stopped short of classifying this particular area as
old-growth, noting that there is a lower density of old trees than is
normally considered necessary for a forest to be strictly considered
old-growth. He believes it must have undergone at least some logging if
very long ago.

Dale looking at large American Beech - photo by Carl Harting

Actually, I’ve just thought of another possible factor in addition to human
intervention that might help account for the low density of older trees.
Perhaps the area contained a lot of American Chestnut trees that would have
been lost in the early 1900's leaving big gaps. Just a speculation.

Another thing that has always been a mystery to me is the lack of hemlock
trees outside of gorge and its deeper tributary ravines. Even in those
riparian areas that do contain hemlocks, there are no large ones like you
see at Cook Forest or other Central Pennsylvania sites. Were they all
harvested at one point? If this were true, I would imagine that there would
now be at least a few younger ones scattered around, but there are not. Is
it because this is simply a different forest type? The geology of the area
is more like that of flat Ohio than mountainous Central PA. Would that
account for it? I'm not at all familiar with this part of the state. The
lack of hemlocks is probably normal for this area. I'm probably just too
used to the Allegheny Mountain forests.

Just below the big woods area down inside the gorge is an area known as
Walnut Flats which we accessed by an old wagon road.   As I've said in a
past report, Walnut Flats contains some of the tallest trees in the park
including two PA height records (American Basswood, 6'5"X127.1'; Slippery
Elm, 9'0"X127.0').

The species content of this area is much different than the big woods area
just on top of the gorge. In Walnut Flats there are numerous American
basswoods, bitternut hickories, white ashes, sycamores, and sugar maples
with a few Slippery Elms and, of course, Black Walnuts scattered about.
Tulips and beeches are plentiful, as above the gorge, but oaks are few. The
old-looking, moss-covered maple pictured in Ed's website report is down
there, as is downed American basswood cutaway whose ~180 rings Dale and Ed
counted. I don't believe that they measured the girth of that log. I'll
make it a point to do so on my next trip. (I found a larger-girthed living
American basswood in another part of the gorge measuring 9'3"X118.4'. It,
too, is ancient looking.)

Rough barked black walnut - photo by Carl Harting

Though Dale balked at classifying the big woods section as old-growth, he
had no trouble considering Walnut Flats and much of the forest down inside
the gorge as such. Here as in many other areas inside the gorge the trees
show a lot of very interesting bark and branching patterns. My two favorite
trees in this area are the maple mentioned earlier and a black walnut tree
with deep large sections of bark peeling off in thick twisted plates. Dale
said that he’d seen that character before but never as pronounce as on that
tree.

Because of the sizes of many of trees, it’s easy to become distracted and
forget to notice some of these more unusual characters that don’t always
appear on the largest trees but that in many ways are a lot more interesting
than sheer size. As I spend more time at McConnells Mill, I’m learning to
appreciate these features more.

We didn’t measure many trees this trip. A number of the ones we did measure
were re-measures. Below is a list of trees measured either on this trip or
on my own recent trips that I haven’t yet posted. I plan post a
comprehensive list of all the trees we’ve measured at McConnells Mill soon.


Species CBH Height Measurer(s)

Black walnut 10.1     110.9     Luthringer
Cucumbertree 10.3     131.6     Frank, Harting, Kelly, Luthringer
N. red oak 12.6     107.5+   Luthringer
Pignut hickory 4.4       96.9       Luthringer
Red Maple       7.9      107.4     Kelly
Sassafras 3.9       63.7       Luthringer
Slippery Elm    9.0      127.0     Kelly
Sugar Maple    8’8”     123.0     Kelly, Luthringer


Slippery Rock Creek Gorge
Rucker Index as of 6/11/2006:

Tulip Poplar             10'9"        146.0'   (Kelly)
White Ash              6'7"         137.7' (Kelly)
Sycamore             9'0"         137.5' (Kelly)
Bitternut Hickory     5'10"        132.7' (Kelly)
Cucumbertree        10'2"        131.6' (Frank, Harting, Kelly, Luthringer)
Am Basswood         6'5"         127.1' (Kelly)
S. Elm                   9'0"         127.0' (Kelly)
N. Red Oak            9'7"         123.1' (Harting)
Sugar Maple           8'8"         123.0' (Kelly, Luthringer)
E. Hemlock             n/a          122.8' (Luthringer)

Rucker Index = 130.85


PA height records in Slippery Rock Creek Gorge Area:

Am Basswood         6'5"         127.1'
Cucumbertree         10'2"        131.6'
S. Elm                    9'0"         127.0'
Black Gum              6'4"        110.6'


Thanks,
Anthony Kelly