PLATE 27. 



LESSER BURDOCK, Ardium Lappa, L, var. minus, Gray. 



Other English names : Bardane, Common Burdock, Clotbur. 

 Other Latin names : Lappa minor, DC. ; Arctium minus, Schk. 



(Noxious : Ont.) 



Introduced. Biennial, from a deep thick tap root. Root leaves large, 

 heart-shaped, downy beneath, somewhat resembling those of Rhubarb, peti- 

 oles hollow. Flowering stem much branched, from 3 to 6 feet high, flowers 

 purple, flower heads numerous, in clusters at the tips of the branches and in 

 the axils of the upper leaves, | inch across, oval-globular ; the scales of the 

 involucre ending with hooks by which the seed-bearing heads become burs 

 and are distributed bv becoming attached to passing animals, etc. Seeds 

 [Plate 56, fig. 62 natural size and enlarged 4 times] oblong-ovoid, trun- 

 cate at each end, flattened, with about 5 elevated longitudinal lines, gen- 

 erally somewhat curved, pale brown with dark transverse zig-zag depressed 

 marks, apical scar circular with a central point, pappus, when present, con- 

 sisting of several rows of short bristles barbed upwards. 



7'ime of Flowering : July to August ; seed ripe September. 

 Propagation : By seed. 



Occurrence : Rich land in the older settled provinces ; common in waste 

 places, by roadsides and in orchards in sod. 



There are two forms of the Burdock found wild in Canada as weeds ; 

 by far the commoner is the one figured in our plate, which has much more 

 numerous and smaller flower heads, with the scales of the involucre shorter; 

 the seeds are darker, sometimes showing hardly any pale brown marks ; the 

 petioles arc hollow, which is not the case in the other and less common form, 

 Arctium Lappa, L., (Lappa major, Gaertn., and L. officinaUs, All., var. 

 major, Gray). This latter has much larger green flower heads, 1J inches 

 across, with the hooked scales more spreading and has longer peduncles. 



Remedy : Cut below the crown or spud out when the ground is wet and 

 soft, either the first year, or before the seeds are ripe in the second. 



56 



