740 WEED FLORA OP IOWA 



Pigweed, winged {Cycloloma platyphyllum) Italy (Arcangeli). 



Plantain {Plant ago aristata) Germany (Bitter). 



Ragweed, small ■ {Ambrosia art emisii folia) Germany (Garcke, 

 I^aubert). 



Eiee cut-grass {Leersia oryzoides) Italy (Arcangeli), Germany 

 (Garcke, Buchenau), France (Acloque), Austria (Neilreich), 

 England (Hooker). 



Sida {Sida spinosa) Germany (Alpers). 



Spanish needle {Bidens hipvnnata) Italy (Arcangeli), Germany 

 (Garcke, Boute), France (Acloque). 



Spanish needle {Bidens frondosa) Italy (Arcangeli). 



Spanish needle {Bidens leucanthus) Germany (Garcke). 



Speargrass {Eragrostis pilasa) Italy (Arcangeli), Germany 

 (Garcke), France (Acloque). 



Speedwell {Veronica peregrina) Italy (Arcangeli), Austria 

 (Neilreich) . 



Sunflower, artichoke {Helianthus tuberosus) Italy (Arcangeli), 

 Germany (Garcke). 



Sunflower, common {Helianthus annuus) Germany (Garcke), 

 Austria (Neilreich). 



Tickle grass {Pamicum capillare) Germany (Alpers, Garcke), 

 France, Italy (Arcangeli), Austria (Neilreich). 



Tickseed {Coreopsis tinctoria) Germany (Bitter). 



Waterweed {Elodea canadensis) Germany (Garcke, Scherer, 

 Weshoff, Bitter), England (Hooker), France (Acloque). 



INDIGENOUS WEEDS COMMON TO THE NORTHERN HEMISPHERE. 



In all probability a few of the weeds here listed have been intro- 

 duced, at any rate their origin is in doubt; some occur in Europe 

 and North America only; those found in Asia are marked (As.). 



Achillea ynillefoliwrn (yarrow) (As.). 



Alopecurus geniculatus (marsh foxtail). 



Anagallis arvensis (pimpernel) (As.). 



Anaphalis margaritacea (everlasting). 



Atri/plex patula var. hastata (orach). 



Barba/rea vulgaris (yellow rocket). 



Bidens cernua (sticktight). 



Capsella bursa-pastoris (shepherd's purse). 



Gerastium arvense (mouse-ear chickweed). 



Convolvulus sepium (morning-glory) (As.). 



