728 



WEED FLORA OF IOWA 



cats '-ear {Hypochaeris radicata) is one of the most common weeds 

 in lawns. There is a common belief that it was introduced from 

 Chile. 



In the Great Basin country, especially in Utah, a large number 

 of the weeds are of European origin. Of the most common of 

 these mention may be made of the brome grasses (Bromus brizae- 

 fomds and B. tectorum), bouncing Betty (Saponaria vaccaria), 

 black medick {Medicago lupvMna), dodders {Cuscuta arvensis and 

 C. epithynmm),- -poison hemlock {Conium maculatum) , moth mul- 

 lein {Veriascum Hattaria), mint {Mentha viridis), Russian thistle 

 {Salsola kali \av. tenuifolia) , horehound {Marrubium vulgare) , 



Fig. 551. Awned Brome Grass (Bromus tectorum). Common In the Great 

 Basin country and California, occasionally In Iowa. 



