Betula nigra catkins long, the male catkins pendulous, the female catkins erect. The fruit is unusual among birches in maturing in late spring; it is composed of numerous tiny winged seeds packed between the catkin bracts. "Betula nigra" is a tree that falls into the family of Betulaceae, which is commonly known as the Birch or Alder Family. This family comprises six genera ("Alnus, Betula, Carpinus, Corylus, Ostrya," and "Ostryopsis)" and includes alders, birches, hornbeams, and hazelnuts. Species within this family, along with "Betula nigra", are shrubs or trees that grow along stream sides or in poorly drained soils throughout the Northern
Northern celestial hemisphere referred to as the Northern Hemisphere. For the purpose of celestial mapping, astronomers may conceive the sky as the inside of a sphere divided into two halves by the celestial equator. The Northern Sky or Northern Hemisphere is therefore the half of the celestial sphere that is north of the celestial equator. Even if this geocentric model is the ideal projection of the terrestrial equator onto the imaginary celestial sphere, the northern and southern celestial hemispheres is not to be confused with descriptions of the terrestrial hemispheres of Earth itself. Northern celestial hemisphere The northern celestial hemisphere, also called the