Cirsium scariosum var. congdonii

(R. J. Moore & Frankton) D. J. Keil

Sida 21: 215. 2004.

Common names: Rosette thistle
Endemic
Basionym: Cirsium congdonii R. J. Moore & Frankton Canad. J. Bot. 45: 1738. 1967
Treatment appears in FNA Volume 19. Treatment on page 158. Mentioned on page 155.

Plants acaulescent or nearly so (with dense rosettes of leaves and cluster of sessile or subsessile heads). Stems absent or very short, simple, stout, fleshy, very leafy. Leaves: blades oblong to oblanceolate or elliptic, shallowly pinnately lobed or sometimes unlobed, longer spines slender, less than 1 cm, abaxial faces green and ± glabrous to white-tomentose, adaxial faces green, glabrous or villous with septate trichomes. Heads 1–many, sessile or subsessile, crowded. Involucres 2–3 cm. Phyllaries: outer and mid lanceolate to ovate, spines slender, 1–4 mm; apices of inner linear-acuminate, often twisted, entire or minutely toothed. Corollas pink to reddish purple, 22–30 mm, tubes 10–15 mm, throats 5–7.5 mm, lobes 4–7 mm; style tips 3–5 mm. Cypselae 4–4.5 mm; pappi 17–28 mm. 2n = 34 (as C. congdonii).


Phenology: Flowering summer (Jun–Aug).
Habitat: Meadows, springs, stream banks
Elevation: 1500–3100 m

Discussion

Variety congdonii grows from the Sierra Nevada of western Nevada and eastern California to the San Bernardino Mountains of southern California.

Selected References

None.

Lower Taxa

None.