288 NEW YORK STATE MUSEUM 



trated here, but is usually larger in every way, the beaks of the bur being 

 almost straight and more or less divergent. 



The Clotburs (Xanthium) are usually placed in the Ragweed family 

 (Ambrosiaceae) but here retained for convenience in the Sunflower family. 



Ironweed 



Vernonia noveboracensis (Linnaeus) Willdenow 



Plate 227 



Stems erect, stiff, coarse, simple or somewhat branched, 3 to 9 feet 

 high from a perennial root, roughish-pubescent or nearly smooth. Leaves 

 alternate, narrowly oblong to lanceolate, pointed or elongated at the apex, 

 narrowed at the base into slender petioles, or the upper leaves nearly sessile, 

 margins serrulate, 3 to 10 inches long, one -half to 1 inch wide. Inflorescence 

 consisting of several or many heads of deep-purple flowers, arranged in a 

 loose, cymose panicle at the summit of the leafy stem. Each head one- 

 third to one-half of an inch broad and containing twenty to forty flowers. 

 Involucre of brownish purple or greenish bracts, overlapping in several 

 series, with long, spreading and slender tips, usually two or three times 

 their own length. Flowers all tubular with a regular, five-toothed corolla. 

 Pappus purplish in color. 



In moist soil and low grounds, Massachusetts to Pennsylvania and 

 Aiissouri, south to North Carolina, West Virginia and Mississippi. Flow- 

 ering in late summer and early fall. In New York, not common north 

 of the lower Hudson valley region and the coastal plain. 



Joe-pye Weed; Purple Boneset 



Eiipatorium purpureum Linnaeus 



Plate 228 



Stems tall, smooth, often purplish and glaucous, frequently straight, 

 simple or branched only at the summit, 3 to 10 feet high from a perennial 

 root. Leaves ovate, oval or ovate-lanceolate, petioled. toothed, 4 to 13 

 inches long, one-half to 3 inches wide, veiny and sometimes slightly 

 pubescent on the under side of the leaf, arranged in whorls of threes to 



