Prunus spinosa the more shrubby habit with stiffer, wider-angled branches of "P. spinosa"; in summer by the relatively narrower leaves of "P. spinosa", more than twice as long as broad; and in autumn by the colour of the fruit skin purplish black in "P. spinosa" and yellow or red in "P. cerasifera". "Prunus spinosa" has a tetraploid (2"n"=4"x"=32) set of chromosomes. The specific name "" is a Latin term indicating the pointed and thornlike spur shoots characteristic of this species. The common name "" is due to the thorny nature of the shrub, and its very dark bark. The word commonly used
Prunus pensylvanica Prunus pensylvanica Prunus pensylvanica, also known as bird cherry, fire cherry, pin cherry, and red cherry, is a North American cherry species in the genus "Prunus". "Prunus pensylvanica", grows as a shrub or small tree, usually with a straight trunk and a narrow, round-topped crown. It grows tall and in diameter. Trees up to tall have been found growing in the southern Appalachians, with the largest found on the western slopes of the Great Smoky Mountains. Its foliage is thin, with leaves long and wide. Flowers occur in small groupings of five to seven with individual flowers across. The fruit