Betula alnus var. rugosa DuRoi Dataset GBIF Backbone Taxonomy Rank VARIETY Classification kingdom Plantae phylum Tracheophyta class Magnoliopsida order Fagales family Betulaceae genus Alnus species Alnus incana Name Homonyms Betula alnus var. rugosa Du Roi Betula alnus subsp. rugosa Du Roi Betula alnus var. rugosa DuRoi