DIPSACACEAE TEASEL FAMILY 
WILD TEASEL 
Dipsacus sylvestris Huds. 
The Teasel family is small, and all its members are natives 
of the Old world. 
Wild Teasel was introduced into this country from Europe 
and is found in waste places 
and along roadsides from 
Maine and Ontario to North 
Carolina, west to Illinois. It is 
gradually spreading farther 
west and south. Though com- 
mon locally in a number of 
places in IIlinois, it is not gen- 
eral throughout. 
This is a biennial 
herb, producing the 
first year only a ros- 
ette of leaves that re- 
main green all winter, ; 
and the second year 
a stout stem 3-6 feet z 
high. Stems, pedun- 
cles, midribs of the leaves and the involucre below the inflores- 
cence are armed with numerous prickles. The opposite leaves are 
sessile and usually the upper have their bases grown together to 
form a sort of cup which is often filled with water after rains. 
The upper leaves are also acuminate and generally entire but 
the lower, often 1 foot long, are obtuse, round toothed or some- 
times pinnately cleft at the base. 
The flowers bloom from July to September, progressively 
upward from the base of the inflorescence. The heads are at first 
ovoid, become cylindric, and at length are 3-4 inches long. The 
linear leaves of the involucre are curved upward and as long as the 
head or longer. Each flower is accompanied by a chaffy bract and 
also a 4-leaved calyxlike involucel, and both of these structures 
are spiny pointed. The calyx itself is grown fast to the ovary and 
is cup shaped above. The blue or lilac corolla, attached above 
the ovary, is tubular, 2-lipped and 4-lobed. Four stamens are 
attached to the tube. The fruit is an akene. 
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