Rubus plus is a rare North American species of brambles in the rose family. It grows in the states of Michigan, Indiana, and Wisconsin in the north-central United States.Biota of North America Program 2014 county distribution map Bailey, Liberty Hyde 1947. Flora of Kalamazoo County, Michigan. Vascular Plants 132–133, figure 2
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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