PLATE 3. 



GREEN TANSY-MUSTARD, Sisymbrium incisum, Engelm., var. filipes. Gray. 



Other English name : Cut-leaved Tansy-Mustard. 

 Other Latin names : Sophia incisa (Engelm.) Greene. 



(Noxious: N.W.) 



Native. Biennial. In the first season a rosette of finely divided leavei^ 

 lying on the ground. Stems, 3 to 4 feet, erect, widely branching at the top and 

 bearing an enormous number of narrow, smooth, slightly curved pods from 

 J to I inch long on slender spreading pedicels. Whole plant bright green 

 and somewhat glandular. Leaves pinnately divided and the pinnae again 

 once to twice divided into linear-oblong entire or toothed segments. Flowers 

 yellow, one-eighth of an inch across in elongated racemes. Seeds [Plate 53, 

 fig. 2— natural size and enlarged 8 times] very small, -^r, of an inch long, 

 reddish brown, minutely roughened with mucilaginous hairs, shedding out 

 very easily. 



Time of Flowering: July; seeds ripe August. 



Propagation : By seeds. 



Occurrence : In crops grown on stubble and on imperfectly cultivated 

 summer-fallows. 



Injury : A coarse unsightly weed and a gross feeder. 



Remedy : Fall and spring cultivation and hand-pulling. 



The Geay Tansy-Mustaed, Sisyvibrium incisum, Engelm., var. Hart- 

 wegianuTU, Watson, is also a tall coarse biennial plant with much divided 

 foliage like the above, but diifers by being covered with short gray pubescence 

 and its more erect habit of growth. It has pods only \ inch long, all crowded 

 close to the slender ascending branches which form a narrow spire. The 

 Gray Tansy-Mustard is the commoner and more widely distributed plant of 

 the two. It flowers and ripens its seed some weeks later. These two coarse 

 biennials grow only from seed, but they throw out long branches from their 

 white tap roots and draw nourishment from a wide area. As they stand up 

 considerably above the crop, they are a conspicuous advertisement of neg- 

 ligent farming. 



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