Prenanthes racemosa
glaucous rattlesnakeroot, glaucous white lettuce, prenanthe à grappe, purple rattlesnake-root
erect, green or light purple, simple, (stout), glabrous and glaucous proximally, setose or hispid distally.
proximal usually present at flowering;
petioles broadly winged, (1–15 cm);
blades broadly oblanceolate to spatulate, 4–25 × 1–8 cm, coriaceous, bases attenuate, clasping, margins entire or weakly denticulate, apices obtuse or rounded, faces glabrous;
mid cauline sessile, clasping;
distal sessile and reduced.
campanulate, 11–12 × 4–7 mm.
9–29;
corollas usually pinkish, sometimes white or lavender, 7–13 mm.
7–14, green to purple, lanceolate to linear, 10–12 mm, margins scarious, sparsely to densely setose.
of 8, dark green to purple, narrowly triangular-subulate bractlets 2–4 mm, coarsely setose.
(ascending) in (elongate) narrowly racemiform or paniculiform arrays.
golden brown, sub-cylindric, subterete, 5–6 mm, indistinctly 8–12-ribbed;
pappi pale yellow, 6–7 mm.
= 16.
Prenanthes racemosa
Prenanthes racemosa is recognized by its erect, stout, simple habit, glaucous stems, spatulate proximal leaves with broadly winged petioles and rounded to obtuse apices, heads borne in narrow racemiform arrays, purple and hairy phyllaries, and usually pinkish corollas. It is most similar to P. aspera, which differs in its generally smaller stature, more hirsute stems, leaves that are hispid abaxially, proximal leaves usually withered by flowering, and creamy white or yellow corollas. Hybrids between P. racemosa and P. trifoliolata, known as P. ×mainensis, occur in the northeastern United States and southeastern Canada (see discussion under P. trifoliolata).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
Flora NW
IL Wildflowers
MI Flora
MN Wildflowers
MO Plants
PNW Herbaria
WildflowerSearch
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USDA Plants Database
