COMPOSITE FAMILY COMPOSITAEt 
ILLINOIS IRONWEED 
Vernonia illinoensis Gleason 
The Illinois Ironweed is common on prairies and in other open: 
places from Ontario to Illinois, Kentucky and Texas. It is peren-= 
nial and has a stout, densely hairy stem that grows 3-6 feet high! 
and is quite leafy. The leaves: 
are quite similar and densely, 
hairy on the lower surface. 
This plant blooms in bril-| 
liant display from August tor 
October. The inflorescence is: 
usually quite compact as the; 
heads have short peduncles.: 
The involucre is rather short’ 
cylindric and its bracts are: 
more or less hairy, purplish and: 
arranged in several series. The: 
receptacle is flat and _ noty 
chaffy. The 30-60 red-purple flowers of each head: 
are tubular and perfect. The akenes are cylindri-) 
cal and smooth or nearly so. The pappus is purple: 
and double, the outer part consisting of small! 
scalelike bristles and the inner part of a large: 
number of long threadlike bristles. 
The Western Ironweed, Vernonia fasciculata: 
Michx., is more often found on low grounds and‘ 
wet prairies, from Ohio to Minnesota, Nebraska and: 
Oklahoma. The blooming season is July to Septem-. 
ber. The plant is about the same size as V. i/linoensis | 
but the stem is smooth or nearly so. The leaves are very } 
narrowly lanceolate and are smooth or nearly so on® 
both sides. They are 3-6 inches long and are usually less than one- 
half inch wide. The heads are smaller than in the Illinois Ironweed, 
being only 20-30-flowered, but otherwise they are similar. 
The New York Ironweed or Flat Top, Vernonia noveboracensts | 
Willd., has somewhat hairy to smoothish stems that rise 3-9 feet! 
from the moist soil of wooded bluffs in the Illinois river system. The 
3-10-inch leaves are lanceolate or narrowly oblong, fine toothed, more: 
or less hairy beneath and narrowed into petioles. The peduncled . 
heads are mostly 30-40-flowered, deep purple or rarely white. Bracts : 
of the hemispheric involucre are brownish purple or greenish and_ 
have spreading awl-shaped tips usually 2-3 times their own length 
The pappus is purplish or rarely green. 
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