This is a variable polyploid species, as currently defined to include R. micrantha Borrer ex Sm. (2n = 28, 35, 42), which has been treated as a variety. See W and FNA 9 for recent notes on nomenclature and taxonomy. In Ky. most plants have been identified as micrantha, and there has also been confusion with canina; further revision is desriable. These roses often persist from plantings, but it is generally not clear from colls. if the plants are truly naturalized from seed.