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
White-winged swallow White-winged swallow The white-winged swallow ("Tachycineta albiventer") is a resident breeding swallow in tropical South America from Colombia, Venezuela, and Trinidad south to northern Argentina. It is not found west of the Andes. This swallow is largely non-migratory. The genus "Tachycineta" was established for this group of swallows by German ornithologist Jean Cabanis in 1850. The genus name derives from Ancient Greek "takhukinetos", "moving quickly"; the specific name "albiventer" is from Latin "albus", "white", and "venter", "belly". This swallow is monotypic, and no subspecies are currently recognized. The adult white-winged swallow is long and weighs . It has iridescent blue-green