Silphium perfoliatum f. perfoliatum Dataset GBIF Backbone Taxonomy Rank FORM Classification kingdom Plantae phylum Tracheophyta class Magnoliopsida order Asterales family Asteraceae genus Silphium species Silphium perfoliatum Name Homonyms Silphium perfoliatum f. perfoliatum Silphium perfoliatum subsp. perfoliatum Silphium perfoliatum var. perfoliatum