160 



WEED FLORA OF IOWA 



Fig. 90- A. Distribution of Rocket. 



smaller, lobed, or entire ; flowers white or yellowish-white with dark 

 veins; fruit an oval, elongated silique containing many, more or 

 less compressed, seeds in 2 rows. 



Distribution. — A native of western Asia and the Mediterranean 

 region, but cultivated as a salad plant and often an escape. Intro- 

 duced into Iowa with alfalfa seed in Woodbury, Plymouth, 'Brien, 

 Clay, Mitchell, Pottawattamie, Mills, Ida, and Sac counties. 



Extermination. — The weed can be exterminated by cutting the 

 plants off a few inches below the surface of the ground or by giving 

 thorough cultivation. 



Hare 's-ear Mustard (Conringia orientalis (L.) Dumort). 



Description. — Slightly succulent annual; leaves light green, ses- 

 sile, obtuse, racemes becoming elongated in fruit; petals much 

 longer than the sepals ; pods long, linear 4-angled, spreading ; coty- 

 ledons incumbent. 



Distribution. — Common eastward and appearing in the Missis- 

 sippi valley; occurring in Woodbury, Webster and Page counties 

 and probably in many other places in Iowa. 



Extermination. — Easily exterminated by cultivation. 



