MICHIGAN WEEDS. 



421 



Fig. 215 (187). 



Beggar Ticks. Stick-tight. Bidens 

 frondosa L. An erect, branched, mostly 

 smooth, annual, 60-250 cm. high; leaves thin, 

 3-5 divided, the sections narrow; rays none; 

 achenes flat, oval, the two slender awns barbed 

 downward. Damp soil. 



Fig. 216 (188). 



Star Thistle. Centaur ea sol st itiali s L. A 

 straggling plant, gray, with loose wooly hairs, 

 30-50 cm. high; stem leaves small, narrow, each 

 with one margin growing down the stem; heads 

 about 1.5 cm. broad, some of the stout spiny 

 scales yellow, spreading, 12-18 mm. long. 



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