360 WEED FLORA OF IOWA 



the roots off with a small spade. This will effectually destroy the 

 plant. In Europe, it is sometimes recommended as a forage plant 

 but it is of doubtful value. 



Mayweed or Dog Fennel {Awthemis cotula L.). 



Description. — ^An acrid, branching, strong-scented perennial, 

 white ray flowers; plants 1-2 feet high; leaves pinnately dissected; 

 solitary and many-flowered, outer ray flowers pistillate, fertile, or 

 neutral ; disk flowers yellow, small, and tubular ; involucre of num- 

 erous, small, dry scarious scales;, achenes small, tuberculate; pap- 

 pus roughened, none, or merely a minute crown. 



Distribution. — This weed is native to Europe; early introduced 

 in the United States, now. common from the Atlantic to the Pacific. 

 In Iowa more common in n6rth,ea§tem part than westward; es- 

 pecially abundant in some gaxdeiis and along roadsides. 



Extermination. — ^A weed easily exterminated by cultivation. It 

 is especially common in clover seed in eastern United States. 



Clark and Fletcher recommend as follows : ' ' Clean up the waste 

 J)l4feefe about the farmyards and seed to permanent grass that will 

 take full possession of the soil to the exclusion of this and other 

 weeds. This plant is usually prevalent in gardens fertilized with 

 manure from city stables." 



