DESCRIPTIVE MANUAL 



165 



Fig. 92-A. Distribution of Hedge Mustard. 



Chemical C omposition.-^ Aceovding to the University of Minne- 

 sota it is as follows :* 



Tumbling Mustard {Sisymbrium aiUssimum L.). 



Description. — ^A leafy, branclied annual from 1-4 ft. high, lower 

 leaves runcinate, pinhatifid, irregularly toothed, or wavy margined, 

 upper leaves smaller, threadlike. 



Distribution. — This weed is native to east Europe. It has become 

 widely scattered in the northern states, particularly in the west from 

 Minnesota to Washington and in Canada. It is widely sca;ttered in 

 Iowa in the vicinity of railroad watering tanks, elevators and stock- 

 yards. It is less common in the southern half of the state. 



Extermination. — The young mustard plants are easily killed by 

 cultivation. They are likely to occur in some commercial seed like 

 timothy, therefore, sow only clean seed. 



•Snyder: Bull. Minn. Agr. Exp. Sta., 101. 



