Betula alleghaniensis
The yellow birch was first described by François André Michaux in 1812 as "Betula lutea". In 1904, Nathaniel Lord Britton described what he considered to be a new closely related species of birch as "Betula alleghaniensis", differing from "B. lutea" by its shorter fruiting scales and mostly cordate (vs. rarely cordate) leaf bases. After comparing the descriptions and illustrations of "B. lutea" and "B. alleghaniensis", Merritt Fernald found the latter to be identical to "B. lutea", but did confirm the existence of two varieties. Later, the name "Betula lutea" was determined illegitimate as it was superfluous to the older name that Michaux had listed as a synonym, "Betula excelsa" (1789). Additionally, the type specimen of "Betula excelsa" was found not to be a yellow birch, making "Betula alleghaniensis" the oldest and correct replacement name for the illegitimate "B. lutea".