Prenanthes sagittata

(A. Gray) A. Nelson in J. M. Coulter and A. Nelson

in J. M. Coulter and A. Nelson, New Man. Bot. Centr. Rocky Mt., 592. 1909.

Common names: Arrowleaf snakeroot
Endemic
Basionym: Prenanthes alata var. sagittata A. Gray in A. Gray et al., Syn. Fl. N. Amer. 1(2): 435. 1884
Synonyms: Nabalus sagittatus (A. Gray) Rydberg
Treatment appears in FNA Volume 19. Treatment on page 270. Mentioned on page 265, 268.

Plants 8–75 cm; taproots short, thick and tuberous or long and slender, fascicled. Stems erect, greenish and mottled purplish, ± glabrous or proximally glabrate, distally glabrous. Leaves: 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. Heads in narrow, elongate paniculiform or racemiform arrays. Calyculi 5–7, green, subulate to narrowly lanceolate bractlets 3–8 mm (longest 2/3 lengths of phyllaries), glabrous. Involucres narrowly campanulate (rounded), 7–13 × 5–8 mm. Phyllaries 7–12, green to tan, apices dark, linear-lanceolate, 8–12 mm, margins narrowly scarious, (apices sparsely ciliate), faces glabrous. Florets 10–19; corollas white, 9–15 mm. Cypselae brown, fusiform to oblanceoloid, subterete or angled, 5 mm, indistinctly 7–10-ribbed; pappi pale-yellow, 5–6 mm. 2n = 16.


Phenology: Flowering Jul–Aug.
Habitat: Stream banks, terraces, moist shady places, talus, rock crevices, mixed conifer woodlands
Elevation: 1000–1600 m

Discussion

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.

Selected References

None.

Lower Taxa

None.

No values specified."fine" is not a number.

... more about "Prenanthes sagittata"
not beaked +  and truncate +
linear-lanceolate +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
scarious +
ovate +  and lanceolate +
racemiform +, paniculiform +  and elongate +
indeterminate +  and determinate +
David J. Bogler +
(A. Gray) A. Nelson in J. M. Coulter and A. Nelson +
lobed +, hastate +  and truncate or rounded +
Prenanthes alata var. sagittata +
compound +  and simple +
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
deltate;ovate +
tuberculate +, rugose +, muricate +  and smooth +
triangular;linear-lanceolate or subulate +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
filiform +
Arrowleaf snakeroot +
zygomorphic +, actinomorphic +  and (3-)5-merous +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
fusiform +  and oblanceoloid subterete or angled +
Alta. +, B.C. +, Idaho +  and Mont. +
1000–1600 m +
winged +  and beaked +
dispersed +
Stream banks, terraces, moist shady places, talus, rock crevices, mixed conifer woodlands +
indeterminate +
each +  and sessile +
0.2 cm2 mm <br />0.002 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
cauline +  and basal +
2-carpellate +
pale-yellow +
persistent +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Flowering Jul–Aug. +
connate +  and distinct +
7 +  and 12 +
subequal +  and unequal +
in J. M. Coulter and A. Nelson, New Man. Bot. Centr. Rocky Mt., +
exalbuminous +
greenish and mottled purplish +
glabrous +  and glabrate +
1 +  and 5 +
appendaged +  and truncate +
papillate +
Nabalus sagittatus +
Prenanthes sagittata +
Prenanthes +
species +
5 cm50 mm <br />0.05 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +