Blackberries grow all over the place. I could have gone into a long list of states where this species lives. Or I could say that they just grow in Kalamazoo, where Fernald says one species is found. He lists 194 species, just in the northeast. I can just see him in his office at Harvard, surrounded by mountains of specimen sheets, with a bottle of good stuff at hand. Gleason and Cronquist show us a more sober eleven species. Other experts are scattered across that range. These plants have created a identification puzzle we will never solve. One year's solution is superceded by next year's plants. The variations and hybrids are endless. So with blackberries we will always never know what we've got until it's in our mouth.