Eric Outterson
December 4th, 2009
Natural History of the Berkshires
4:30-6:00
I came into my site expecting little to have changed since I visited two weeks ago. It was not the same, however. The site has now been completely defoliated. I don’t see any leaves left clinging to any branches. I also no longer see the pretty pink sepals of the winged euonymus. The entire site appeared desolate. I did not hear any small mammals moving through the leaves, nor did I hear any birds chirping in these woods.
At the north end of the site, in the depression in the ground there is still a large puddle of standing water. Using a stick, I measured the puddle’s depth to be about 8 inches deep. After I disturbed the wet leafy mass immediately beneath the surface of the puddle, however, I noticed many small bubbles surface. Since I did not smell anything, I assume it was not anaerobic decomposition. Rather, I assume that it was very small amounts of air coming up to the surface. It appears that drainage is very poor here, although movement from the surface to sub-surface may be slow.
I next moved begin examination the largest cottonwood tree at my site. I guessed that the tree stood about 60 feet tall. Precise measurements of width were 171 inches around. This meant the tree had an approximate diameter of about 54 inches and a radius of 27 inches. In this examination, I began to core the tree and slowly but surely bored almost all the way until the tree bark touched the handle of the corer. I thought it was going to be a good haul, and it was. I got far more than a tree core. As soon as I pulled the tree core out of the tree a strong stream of water jetted out from the hole that I punched into the tree. It was as about the size and strength of a garden hose for about one and a half minutes. The volume that came out of the tree was truly astonishing. The flow gradually slowed down to a trickle after about 6 minutes and remained trickling for the next twenty minutes.
Examining the core later I counted somewhere between 53 and 60 different growth rings. The uncertainty is due to variable darkening of the wood, and losing small bits of core in the process of the removal. Since the true radius should be approximately 27 inches, but I only extracted 20, I assumed the width growth to be about the same for every year, and estimate the tree to be between 73 and 83 years old.
Having examined my site in a historical context, I’ve come to see that the site had relatively thin tree cover around 1900 and very thick tree cover about 30 years later. This makes the cottonwood presence make a lot of sense. Typically Populus Deltoides likes to grow in areas with high light. It seems possible that a cottonwood may have grown in around this time.
Looking into the future of this site, however, it seems as if the cottonwoods would not be a part of it. All of the close by land on which trees might grow either already has cover, or is maintained for grass. It seems unlikely that more new cottonwoods will spring up. The trees that seem likely to continue on in the site are the maples there. Since there are no white birch in the vicinity it seems unlikely that Williamstown’s primary first succession species will take hold there. I see many small maples throughout this site, so I’m inclined to believe that as soon as one of the large cottonwoods or black locusts falls, there will be maple to takes its place.
The winged euonymus, buckthorn, barberry, wild garlic mustard, and dames rocket all make up a large portion of the ground cover, and seem unlikely to disappear. I imagine that it we came back in 100 years we would see a more maple heavy forest with a mix of invasive exotics on the floor or the woods. Ultimately, however, the future of the species at the Stetson Parking lot woods, will be entirely determined by what humans do with it. Evidenced by the three large visible stumps in the woods, people have been culling the trees here for one reason or another. There’s no reason to suspect anyone is going to stop now.