Revisiting the black birch

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Revisiting the black birch

Post by dbhguru » Wed Nov 04, 2020 6:04 pm


Back in 2016, I started a project to gather height measurements on Betula lenta across as much of that species range, for which I could get data. I began the project because I was seeing the species locally achieving greater heights than the all the Internet and book sources that describe the species, including the most prestigious, like Silvics of North America. The black birch is commonly described as reaching heights of 50 to 60 feet. A few sources give a maximum of 70 feet, and a couple give between 70 and 80. Yet, I could walk out my back door and easily beat those numbers. The rest is history.

Today, Monica and I took a stroll up the stream that runs in back of our house, and on the way back, I decided to measure a birch that I had previously measured, but not this time of year when the crown is fully visible. Well, to make a long story short, the birch is 96.5 feet tall. There is another slightly farther up the trail that reaches 94.3 feet, and just down a small hill outside our back door, there are three over 90 feet, 99.8, 99.3, and 90.0. Within a mile long swath of forest following the brook, Jared Lockwood and I have measured at least. 25 blacks to over 90 feet, two of which exceed 100. The story is much the same in many other parts of the range of the species, and we have that one that Erik Danielsen measured on Long Island to a little over 121 feet, if my memory serves me correctly.

In the southern Apps, Brian Beduhn has reported many blacks over 100 feet. PA and Ohio have them up to around 115, and so on. So, there is absolutely no debating the matter. Other sources have really short-changed the species. So what's to be done to put the record straight?

It could be worthwhile if we officially began species dimension index. The index could be qualified by geographical area and species. We could figure out a consistent naming scheme. This would be a useful addition to the family of Rucker indices.


Robert T. Leverett
Co-founder, Native Native Tree Society
Co-founder and President
Friends of Mohawk Trail State Forest
Co-founder, National Cadre

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