Betula alleghaniensis colored, peeling bark of yellow birch. For young trees where bark has not yet developed, yellow birch can also be identified by its hairy buds and stems; sweet birch has hairless buds. 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
Northern Hemisphere Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North Pole. Owing to the Earth's axial tilt, winter in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer lasts from the June solstice through to the September equinox (typically September 23 UTC). The dates vary each year due to the difference between