COMPOSITAE (COMPOSITE FAMILY) 497 



Means of control 



Mugwort has to be grubbed out ; or, if the ground is sufficiently 

 soft to relax its hold on the perennial roots, the plants may be 

 hand-pulled. On cultivated ground the weed is destroyed by the 

 required tillage. 



BIENNIAL WORMWOOD 



Artemisia biennis, L. 



Other English names: False Tansy, Bitterweed. 



Native and introduced. Biennial. Propagates by seed. 



Time of bloom : August to October. 



Seed-time: September to November. 



Range: Nova Scotia to the Northwest Territory, southward to 



Pennsylvania, Tennessee, and Missouri. 

 Habitat: Stubble fields, roadsides, and waste places. 



Probably the most common of the Wormwoods ; frequently a 

 tenant of vacant city lots. Stem one to four feet tall, erect and 

 strict, the branches rather short and held nearly upright. Leaves 

 smooth on both sides, dark green, twice pinnatifid, with oblong to 

 linear, toothed, and pointed segments, the lower with petioles, the 

 upper sessile and with fewer lobes or occasionally quite entire ; 

 they are without odor unless bruised. Heads in short, crowded, 

 axillary clusters, erect, sessile, about an eighth of an inch broad, 

 the involucral bracts green with scarious margins, the central 

 flowers only producing seed. 



Means of control 



Hoe-cutting or hand-pulling of autumn plants ; close cutting of 

 flowering stalks before seed development. Infested stubbles should 

 be given surface cultivation or be mowed before the heads mature. 



ANNUAL WORMWOOD 

 Artemisia dnnua, L. 



Introduced. Annual. Propagates by seeds. 

 Time of bloom : July to September. 

 Seed-time: August to October. 

 Range : Ontario to Tennessee and Kansas. 

 Habitat: Fields, roadsides, waste places. 



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