Betula pendula grown for forest products such as lumber and pulp, as well as for aesthetic purposes and ecosystem services. It is sometimes used as a pioneer and nurse tree elsewhere. Silver birch wood is pale in colour with no distinct heartwood and is used in making furniture, plywood, veneers, parquet blocks, skis, kitchen utensils and in turnery. It makes a good firewood that produces a good heat when burnt but is quickly consumed by the flames. Slabs of bark are used for making roof shingles and strips are used for handicrafts such as wooden footwear and small containers. Historically, the bark
Northern rough-winged swallow Northern rough-winged swallow The northern rough-winged swallow ("Stelgidopteryx serripennis") is a small, migratory swallow. It is very similar to the southern rough-winged swallow, "Stelgidopteryx ruficollis". The genus name, "Stelgidopteryx", is from Ancient Greek and means "scraper wing" and the species name, "serripennis", is derived from Latin and means "saw feather". In the common name, "rough-winged" refers to the serrated edge feathers on the wing of this bird; this feature would only be apparent when holding this bird. Six subspecies of the northern rough-winged swallow are currently recognized. It has been proposed that another race be recognized, "aphracta", but this is