50. 



SMALL RAGWEED (Ambrosia artemisiaefolia L.) 

 This weed is a puberulent or hirsute annual, branched, one to 

 three feet high; leaves thin, once to twice pinnatifid; the upper 

 leaves are alternate, the lower, usually opposite, pale or canescent 

 beneath. Flowers monoecious, the staminate above and the pis- 

 tillate in the lower axils of the leaves. The fertile heads are 

 obovoid or globose. Short beaked. Four to six spined. 



BURDOCK (Arctium Lappa L.) 



A coarse, branched biennial from a foot to three feet high; 

 hairy ; leaves large, roundish or heart-shaped, thin, obtuse, entire 

 or dentate, floccose tomentose beneath. Petioles deeply fur- 

 rowed, heads of purplish or whitish flowers, clustered or some- 

 what corymbose. The involucre surrounding the flowers (heads) 

 are lengthened into hooked tips, glabrous or slightly cottony. 



Where burdocks are allowed to grow freely the fruit clings 

 to the fleece of animals, often forming large balls which may be 

 found on the tails of cattle and horses. When they are common 

 where sheep pasture the burdocks work into the wool which 

 soon becomes of little value. The plant is enormously produc- 

 tive. 



