COMPOSITE FAMILY COMPOSITAE 
BLUE LETTUCE 
Lactuca floridana (L.) Gaertn. 
The Blue Lettuce grows in moist open places or moist woods 
from New York and Pennsylvania to Nebraska and southwest, 
blooming from July to September. The stem is rather stout, 
smooth, 3-7 feet high 
and leafy up to the large 
inflorescence. Like all 
species of wild Lettuce, 
it contains an abundance 
of milky juice. The 
leaves are smooth above 
but somewhat hairy on 
the veins beneath. 
are borne on scaly pe- 
duncles, and the flowers, 
with strap-shaped cor- 
ollas 5-toothed at the 
end, are blue. The bracts 
of the involucre are in 
several series, the outer 
much smaller than the 
inner. The akenes are 
thick, somewhat flat- 
tened, and narrowed at 
the end into a distinct 
beak which supports the 
bristly white pappus, well adapted for wind dissemination. 
The Hairy-veined Blue Lettuce, Lactuca villosa Jacq., is 2-6 feet 
tall and its leaves are 4-6 inches long, sessile and clasping. They 
have short stiff hairs on the veins beneath, hence the common name. 
The Tall Blue Lettuce, Lactuca spicata (Lam.) Hitchc., is also 
common in moist soil. The smooth stout stems are 3-12 feet high 
and are leafy to the inflorescence. The leaves are sometimes entire 
but are more often variously toothed and lobed. They are mostly 
sessile but the lower are often narrowed into short-margined petioles. 
They are 5-12 inches long, 2-6 inches wide, and are smooth on both 
sides or somewhat hairy on the veins below. The green heads are 
very numerous, about one-quarter inch broad and tipped with dull 
purple to whitish rays. The akenes are oblong and narrowed above 
into a short beak. The pappus is brown. 
390 
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