162 FARM WEEDS OP CANADA 



Fireweed (Erechtites hieracifolia (L.) Raf.) is a tall rank- 

 smelling annual, with general habits of growth like some varieties 

 of groundsel. The branched stem is succulent and character- 

 istically striate. The flower heads are numerous, small, whitish 

 and conspicuously swollen at the base before opening. 



The seed is small, linear-oblong, tapering at the end and 

 bearing a thick pappus of fine, soft, white hairs. 



The common name, Fireweed, comes from the fact that 

 this weed often occurs on land that has been swept by fire. 



TRIBE CYNAREAE 

 LESSER BURDOCK (Arctium minus Bernh.) 



Other English names: Bardane, Common Burdock, Clotbur. 



Other Latin names: Lappa minor DC., Arctium Lappa L., 

 var. minus Gray. 



Introduced from Europe. Biennial, from a deep, thick, 

 taproot. Root-leaves large, heart-shaped, downy beneath, 

 somewhat resembling those of rhubarb, footstalks hollow. 

 Flowering stem much branched, from 3 to 6 feet high. Flowers 

 purple, flower heads numerous, 3/4 inch across, in clusters at the 

 tips of the branches and in the axils of the upper leaves, oval- 

 globular; the scaly bracts surrounding the flower-heads ending 

 with hooks, by which the seed-bearing heads become burs and 

 are distributed by adhering to passing animals. 



The seed (Plate 76, fig. 87) is about 1/4 of an inch long, pale 

 brown with dark, transverse, zigzag, depressed marks, oblong- 

 ovoid, cut off abruptly at each end, flattened, with about 5 

 longitudinal ridges generally somewhat curved; apical scar 

 circular with a central point; pappus, when present, consisting 

 of several rows of short bristles, upwardly barbed. 



