COMPOSITAE (COMPOSITE FAMILY) 497 
Weans of control 
Mugwort has to be grubbed out; or, if the ground is sufficiently 
ioft to relax its hold on the perennial roots, the plants may be 
iand-pulled. On cultivated ground the weed is destroyed by the 
‘equired tillage. 
BIENNIAL WORMWOOD 
Artemisia biénnis, 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 
‘enant 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 
inear, toothed, and pointed segments, the lower with petioles, the 
ipper sessile and with fewer lobes or occasionally quite entire; 
they are without odor unless bruised. Heads in short, crowded, 
uxillary clusters, erect, sessile, about an eighth of an inch broad, 
the involucral bracts green with scarious margins, the central 
lowers only producing seed. 
Ueans of control 
Hoe-cutting or hand-pulling of autumn plants; close cutting of 
lowering stalks before seed development. Infested stubbles should 
de 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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