Betula lenta as long as the tree lives, but the individual bark layers become indiscernible after roughly 250 years of age. "Betula lenta" was used commercially in the past for production of oil of wintergreen before modern industrial synthesis of the oil; the tree's name reflects the wintergreen scent of the shoots. The sap flows about a month later than maple sap, and much faster. The trees can be tapped in a similar fashion, but must be gathered about three times more often. Birch sap can be boiled the same as maple sap, but its syrup is stronger (like molasses). The leaves
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