Woolly Burdock (Arctium tomentosum P. Mill.) Burdock is also sometimes spelled Burrdock.  Division - Magnoliaphyta Class - Magnoliopsida Subclass - Asteridae Order - Asterales Family - Asteraceae Genus - Arctium  This is a biennial thistle. It can be differentiated from lesser burdock by the hairs on the flower buds.      Taxonomic List List by Scientific Name List by Common Name |