Rubus sewardianus is a rare North American species of brambles in the rose family. It has been found only in the state of Virginia in the eastern United States.Biota of North America Program 2014 county distribution mapFernald, Merritt Lyndon 1945. Rhodora 47(557): 154–156, plates 894–895 includes photos of type specimen at Harvard University Herbaria
The genetics of Rubus is extremely complex, so that it is difficult to decide on which groups should be recognized as species. There are many rare species with limited ranges such as this. Further study is suggested to clarify the taxonomy.Flora of North America, Rubus Linnaeus, 1754. Bramble
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