Betula glandulosa to tall, often forming dense thickets. The trunks are slender, rarely over diameter, with smooth, dark brown bark. The leaves are nearly circular to oval, long and broad, with a toothed margin. The fruiting catkins are erect, long and broad. It is closely related to the dwarf birch ("Betula nana"), and is sometimes treated as a subspecies of it, as "B. nana" subsp. "glandulosa". It is distinguished from typical "B. nana" by the presence of glandular warts on the shoots and longer leaf petioles. Hybrids with several other birches occur. Betula glandulosa Betula glandulosa, the American dwarf birch, also known
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