Betula papyrifera tree. The seeds of paper birch are an important part of the diet of many birds and small mammals including chickadees, redpolls, voles, and ruffed grouse. Yellow bellied sapsuckers drill holes in the bark of paper birch to get at the sap, this is one of their favorite trees for feeding on. The species is considered vulnerable in Indiana, imperiled in Illinois, Virginia, West Virginia and Wyoming, and critically imperiled in Colorado and Tennessee. "Betula papyrifera" has a moderately heavy, white wood. It makes excellent high-yielding firewood if seasoned properly. The dried wood has a density of and an energy
Northern celestial hemisphere Northern celestial hemisphere The northern celestial hemisphere, also called the Northern Sky, is the northern half of the celestial sphere; that is, it lies north of the celestial equator. This arbitrary sphere appears to rotate westward around a polar axis due to Earth's rotation. At any given time, the entire Northern Sky is visible from the geographic North Pole, while less of this hemisphere is visible the further south the observer is located. The southern counterpart is the southern celestial hemisphere. In the context of astronomical discussions or writing about celestial cartography, this celestial hemisphere may also simply then be