Tree nine is a white oak in Rutland, Massachusetts. I gave it that number when I was tagging trees that had lost a noticeable number of branches in an ice storm in 2008. Tree nine lost about half of its branches, but its neighboring trees lost nearly all of theirs, so tree nine ended up growing about as much per year in the four years after the storm as it had in the three years before the storm. More sunlight compensated for having many fewer leaves.
Tree nine has been alive for a century, producing its thickest growth rings early in its life, but its growth declined steadily throughout its life. What happened?
The answer is simple. Nothing. Under constant, ideal conditions, any tree would have thick growth rings at first, with a steady decline in ring thickness throughout their lives. That’s the natural geometry of tree growth, as reflected in growth rings. Each year, a bigger tree makes more wood, but each year, it has to distribute that wood just inside the surface of a larger body (yes, the tree is a body). It might not be obvious how that will affect the width of each ring, year to year, but the result, both empirical and theoretical, is a steady decline in ring width each year (if you care, the decline follows a negative exponential curve).
So tree nine, in general, followed an expected pattern of growth. But there was also a whole lot of variation. Conditions were not constant, often not ideal, and sometimes destructive. Life in the forest is hard. Yet tree nine persevered, and does so to this day.
But the damage from 2008 didn’t heal completely, and eventually the tree was weakened by invading fungi. New wood couldn’t keep up with decaying wood, at least not in one of the major branches. In the summer of 2021, that branch broke, not completely, but more than enough to let the ends of the branch hit the ground, leaves and all.
The base of the branch was still attached to the tree. There was enough good wood to retain a connection between trunk and branch, and good wood is tough stuff. This is what the growth rings look like in the fallen branch:
The connection was not sufficient to sustain life in the fallen branch. The leaves of summer all died, and the stems and buds all died with them. The broken branch, with all the many branches stemming from it, is dead. I will harvest as much of the wood as I can reach to dry and then burn in my stove a year from now. I’ll leave the small twigs and branches and leaves for scavengers and decomposers. I will leave the parts out of reach for insects and woodpeckers.
Tree nine lives on, broken, but not dead. It still stands tall, and the surviving portions of the tree will grow. How long will it live? I have no idea, but I wouldn’t be surprised if it outlives me. Oaks, even wounded ones, can easily outlive people. Oaks give us hope.
Owen D. V. Sholes “Effects of ice storm damage on radial growth of Quercus spp.” The Journal of the Torrey Botanical Society 140(3), 364-368, (1 July 2013)
December 7, 2021 at 10:04 pm
Interesting article. We have walked in the same woods almost daily for 5 years but I rarely notice individual trees. You made me realize each one has a story to tell.
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