COMPOSITAE COMPOSITE FAMILY 
TALL WORMWOOD 
Artemisia caudata Michx. 
Several kinds of Wormwood occur in Illinois, mostly in 
sandy soil, and some of them are very difficult to distinguish. 
The Wormwoods and Sagebrush of the west are Artemisias. 
A flowering plant called 
Broom Rape, which has 
no green tissue, often 
grows as a root para- 
site on Wormwood. 
The Tall Wormwood 
grows only in sandy soil 
from Quebec, Ontario 
and Manitoba to Indi- 
ana, Nebraska and 
Texas, and is especially 
common along Lake 
Michigan. It is one of the 
few plants that can grow 
on dune sand, where 
there is extremely little 
organic food matter. The 
slender stems are much 
branched, very leafy and 
1-6 feet high. 
The lower and basal leaves, as well as those of the sterile 
shoots, are 3-6 inches long, slender petioled and 2-3 times pin- 
nately divided into very narrow linear lobes. The upper leaves are 
sessile or nearly so and pinnately divided or the topmost entire. 
The blooming season is July to September. The numerous 
heads are very small, very short peduncled, mostly nodding, and 
only the outer flowers of each head produce akenes, the inner 
ones being sterile. The involucre is composed of ovate bracts and 
is smooth. There are neither ray flowers nor pappus. 
The Biennial Wormwood, Artemisia biennis Willd., is widely 
distributed nearly throughout the state as a weed. It is not, however, 
strictly biennial, but annual or winter annual, and a better name is 
False Tansy or Bitterweed. It is smooth and the stem is very leafy, 
usually branched and 1-4 feet high. The leaves are 1-3 inches long 
and once or twice pinnately divided into narrow, toothed lobes. 
The very small heads are exceedingly numerous in crowded axillary 
clusters. The flowers are greenish yellow and all produce akenes. 
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