Betula papyrifera the genus "Betula". Several varieties are recognized "Betula papyrifera" is mostly confined to Canada and the far northern United States. It is found in interior (var. "humilus") and south-central (var. "kenaica") Alaska and in all provinces and territories of Canada, except Nunavut, as well as the far northern continental United States. Isolated patches are found as far south as the Hudson Valley of New York and Pennsylvania, as well as Washington. High elevation stands are also in mountains to North Carolina, New Mexico, and Colorado. The most southerly stand in the Western United States is located in Long Canyon in
Blue-winged warbler Blue-winged warbler The blue-winged warbler ("Vermivora cyanoptera") is a fairly common New World warbler, long and weighing . It breeds in eastern North America in southern Ontario and the eastern United States. Its range is extending northwards, where it is replacing the very closely related golden-winged warbler, "Vermivora chrysoptera". The common name "blue-winged warbler" refers to the bluish-gray color of the wings that contrast with the bright yellow body of the male. The name of the genus "Vermivora" means "worm-eating". The genus used to include nine other new world warblers but now includes only the golden-winged warbler and Bachman's warbler