Sunday, February 3, 2013

Hemlock, the patient one

What: Even with the leaves off the trees and sounds (particularly I-89) filtering through the woods with reckless abandon, there's still a peacefulness to the movements of the woods in winter. While walking across the Winooski Bridge I admired the slow undulating flaps of a Cooper's hawk above and the odd oscillations of the water bubbling back and forth off the ice as it came to a halt in front of the dam. The hawk flitted gracefully to the west, cut a quiet line through dense air and alighted on a distant smoke stack.

There's an equal grace and peacefulness to the slow bending of a hemlock - what I call the Winter Tree - under the sway of the wind. Among the conifers, hemlock stands out to me as such a delicate and deeply cold tree. The rich green of the foliage feels more like the shadow of a leaf, like the tree was born in winter only to endure summer each year.

The branch above is about 2 3/4" across

Enduring the summer means slooooow growth. I was out harvesting wood for coasters, and I found a giant old hemlock that had come down across Wool Pullery Brook in South Burlington. I cut the branch from the trees in the photos at the top (about 35' from the trunk) right at the base where it came off of the tree (if the tree were still standing the branch would have been about 25' up). Hemlocks are about the most shade tolerant species, and a single hemlock needle can live for up to 40 years (in part because it can deal with as little as 10% light and still photosynthesize enough for the plant to keep it around; for contrast, white pines are far less tolerant of shade and lose about half their needles each year).

I guess I shouldn't have been, but I was surprised at how ancient the branch was given its size. It was too hard to count the rings by eye so I sanded and finished the "cookie", photographed it, then ramped up the contrast. Each arrow represents 10 years of growth. The rings were extremely tight, and there's a distinct boundary between the heartwood and sapwood (sapwood is the lighter section of rings on the outside). The branch was much less resinous farther out, indicating that the distinction was largely due to the tree needing extra support in holding up that branch for 106 years.

Where: Hemlocks grow at extremes - there are hemlock swamps and there are steep rocky hemlock slopes. It can grow in the shadiest of places, less than about 10% light. This tree was growing along Wool Pullery Brook in Centennial Woods.

No comments:

Post a Comment