Prenanthes racemosa
Prenanthes sagittata
glaucous rattlesnakeroot, glaucous white lettuce, prenanthe à grappe, purple rattlesnake-root
arrow-leaf rattlesnake-root, arrowleaf snakeroot
erect, green or light purple, simple, (stout), glabrous and glaucous proximally, setose or hispid distally.
erect, greenish and mottled purplish, ± glabrous or proximally glabrate, distally glabrous.
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.
proximal present at flowering; petiolate (petioles narrowly winged, sometimes lobed, 5–15 cm);
blades ovate or deltate, 3–10 × 1.5–6 cm, thin, bases hastate to truncate or rounded, sometimes shallowly, palmately lobed, ultimate margins irregularly dentate, faces glabrous;
distal reduced.
campanulate, 11–12 × 4–7 mm.
narrowly campanulate (rounded), 7–13 × 5–8 mm.
9–29;
corollas usually pinkish, sometimes white or lavender, 7–13 mm.
10–19;
corollas white, 9–15 mm.
7–14, green to purple, lanceolate to linear, 10–12 mm, margins scarious, sparsely to densely setose.
7–12, green to tan, apices dark, linear-lanceolate, 8–12 mm, margins narrowly scarious, (apices sparsely ciliate), faces glabrous.
of 8, dark green to purple, narrowly triangular-subulate bractlets 2–4 mm, coarsely setose.
5–7, green, subulate to narrowly lanceolate bractlets 3–8 mm (longest 2/3 lengths of phyllaries), glabrous.
(ascending) in (elongate) narrowly racemiform or paniculiform arrays.
in narrow, elongate paniculiform or racemiform arrays.
golden brown, sub-cylindric, subterete, 5–6 mm, indistinctly 8–12-ribbed;
pappi pale yellow, 6–7 mm.
brown, fusiform to oblanceoloid, subterete or angled, 5 mm, indistinctly 7–10-ribbed;
pappi pale yellow, 5–6 mm.
= 16.
= 16.
Prenanthes racemosa
Prenanthes sagittata
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.)
Prenanthes sagittata is similar to P. alata; it differs in its somewhat smaller stature, heads in narrower and more elongate arrays, and longer calyculi. The ranges of the two species do not overlap.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
Flora NW
IL Wildflowers
MI Flora
MN Wildflowers
MO Plants
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
