56 FARM WEEDS OP CANADA 



THE PIGWEED FAMILY (Amaranthaceae). 



The Pigweeds are a small family of plants, mostly of tropical 

 origin, closely allied to the Spinach family. Each plant produces 

 enormous quantities of small, highly-polished, lens-shaped, more 

 or less margined seeds. The flowers are small and inconspicuous; 

 leaves simple and borne on a stalk. Some of the exotic mem- 

 bers of this family are gorgeously coloured and are grown for 

 their ornamental foliage or flowers, as the Cockscombs (Celosia), 

 Rainbow Amaranth (Amaranthus tricolor L.) and the well-known 

 Love-lies-bleeding (Amaranthus caudatus L.). 



The seeds are borne singly, as in the Spinach family, en- 

 closed in a thin, cartilaginous covering known botanically as 

 a "utricle." Unless closely examined, they may sometimes be 

 confused with rubbed seeds of Lamb's Quarters. The surface 

 of the Pigweed seeds is always more highly polished and smooth- 

 er. The scar is the easiest point for distinguishing them; this 

 is a central point, with a long groove on one side, in Lamb's 

 Quarters and a notch in the margin in the Pigweeds. 



REDROOT PIGWEED (Amaranthus retroflexus L.). 

 Other English names: Rough Pigweed, Chinaman's Greens. 



Introduced from tropical America. Annual, with a rosy- 

 pink tap-root. Stems erect, simple or branched, rough hairy. 

 Leaves on long stalks, ovate, bristle-pointed. Flowers inconspic- 

 uous, numerous, crowded into thick compound spikes at the 

 ends of the branches and in the axils of the leaves. Bracts 

 of the flowers, bristle-pointed, longer than the green calyx 

 divisions. 



The seed (Plate 72, fig. 14) is highly polished, reddish black 

 to jet black, about the same size as that of Lamb's Quarters. 



