המועדפים של taco2000

This tree was growing in a mesic oak woodland on the edge of a moderately tall and steep river bluff within a northern flatwoods complex. It was adjacent to a relatively strong population of Conopholis americana and near a relatively strong population of Monotropa uniflora.

The area is rather far from any man-made structures and at the edge of a very high quality natural remnant that has been under management for decades and another very high quality unmanaged remnant. But the area where this tree was growing has not been managed as far as I know. Considering the associates that I was able to find at this time of year, this tree would seem to have been growing within a respectably high quality remnant natural area as well. However, the area has definitely been impacted by a large road that runs between the mesic bluffs and the adjacent flatwoods.

I can't imagine that this would have been planted here. There is no evidence that anything else may have been planted here. And while this tree could be an escape, it seems like it could very possibly be native on the site. I couldn't locate any other similar trees, although I didn't search intensively.

The bark and twigs are distinct enough that I don't think this could be anything other than a birch species. I initially thought that this couldn't be B. alleghaniensis because the bark was too dark and not peeling and thought it looked like B. lenta. However, B. lenta is very much restricted to the Appalachian Plateau with the closest record being around 300 miles away.

Flora of North America, however, indicates that B. alleghaniensis can have dark and "close" bark. And notes that this species has coarser, more irregular teeth. This latter distinction is subtle, but Flora Novae Angliae makes a more easily assessed distinction stating that B. lenta has leaf margins with >6 teeth per centimeter. I didn't measure this at the time, but it looks as though this has <6 teeth per centimeter, and the teeth do look coarser and slightly irregular. This plus the location and noted variation lead me to think this is B. alleghaniensis.