DESCRIPTIONS OF SOME COMMON WEEDS 



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with stipules; flowers monoecious or dioecious, rarely 

 perfect; calyx free from the one to two-celled ovary 

 which forms the one-seeded fruit; stamens as many as 

 the lobes of the calyx or sometimes fewer ; opposite ; 

 seeds albuminous or ex-albuminous; when albuminous, 

 the radical points upward; cotyledons broad. 



Hemp (Cannabis sativa, L.). A stout, rough, dioecious 

 annual; leaves digitate, five to seven, linear, lanceolate; 

 leaflets coarsely toothed ; inner bark of tough fibers ; stam- 

 inate flowers in axillary, compound racemes, pistillate 

 flowers in erect spikes, consist- 

 ing of the calyx, with a single 

 sepal folded around the ovary; 

 fruit, an achene ; seed oily, em- 

 bryo straight. Widely distrib- 

 uted throughout eastern North 

 America, north of the Gulf 

 States, and the Rocky Moun- 

 tains. 



Common Slender Nettle (Ur- 

 tica gracilis, Ait.). A perennial 

 herb armed with stinging hairs ; 

 stem slender, two to six feet 

 high ; leaves ovate-lanceolate, 

 pointed serrate, three to five- 

 nerved from a somewhat 



rounded base, nearly smooth, . Fi s- 9 7 ; Common nettle (Ur- 

 . , . 1 t ttca gracilis). 



petioles somewhat bristly; 



flowers small, numerous, dioecious, or some with stamin- 

 ate and pistillate flower clusters-; calyx deeply four- 

 parted; stamens four, stellate with calyx; inclosed by it. 

 Common along fences and waste places in eastern North 

 America to Kansas, and the Rocky Mountains to Col- 

 orado. 



Stinging Nettle (Urtica dioica, L.). Like the preceding, 

 stem beset with bristly, stinging hairs ; two to three feet 



