Wild Flowers East of the Rockies 391 



PASTURE THISTLE (Cirsium pumilum) is the 

 thistle that we most often see in fields and pastures. 

 It is one of the largest of the genus, its heads often 

 measuring three inches across. The stem is stout 

 and simple, and grows from 1 to 3 feet high; it is 

 hairy and angular in section and grows from a bien- 

 nial rootstalk. 



The flower heads are very large, two to three and 

 one-half inches across and usually solitary, although 

 frequently two heads grow on the same stalk. The 

 leaves are lance-shaped, green, clasping, rather hairy, 

 pinnatifid and armed with short, stout prickles. Just 

 below the flowers are several small bract-like leaves, 

 also armed with sharp prickles. All this armor tends 

 to discourage pilfering insects from crawling up the 

 stem; should they persist and reach the large invol- 

 ucre, which is also armed, they will find that, in addi- 

 tion, it is slightly sticky, and presents an impenetr- 

 able barrier to their upward progress. This species 

 is common from Me. to Del. and Pa. It blooms from 

 July until Sept. 



COMMON or BULL THISTLE (Cirsium lanceola- 

 tum), although an introduced species has a larger 

 range than the last. It is common in fields and pas- 

 tures and along roadsides from Newfoundland to Ga. 

 and west to Nebr. Its heads are only slightly smaller 

 than those of the preceding; usually but one is found 

 on a plant. The stout stem grows from 2 to 4 feet 

 high. The leaves are rough and bristly above and 

 woolly underneath. 



Although thistles may be foes to those following 

 agricultural callings, they are staunch friends of 

 birds and insects (except crawling ones). The plant 

 fibres and down from the mature heads forms the 

 principal part in the composition of nests of the Gold- 

 finch. 



