Non-technical Description: Clausen’s violet is a stemless perennial forb from a stout, woody rootstalk that lacks rhizomes or runner-like stolons. Leaves are all basal and glabrous at maturity, with 3-14 cm long leafstalks. The elliptic to oval leaf blades are 3-5 cm long and conspicuously longer than wide, have shallowly lobed margins, and are usually heart-shaped at the base. Flowering stalks are 10-14 cm long. The flowers are bilaterally symmetrical with 5 unequal purple or violet petals (the lower 3 petals are larger and usually whitish at the base). All of the petals are glabrous (lacking a whitish beard of hairs) on their inner surfaces. The lowermost petal ends in a bulbous spur that is 2-3 mm long. Fruits are a pale green, ball-like capsule 6.5-10 mm long. Flowering occurs from late April-June (Fertig 2010, Holmgren et al. 2005, Welsh et al. 2008).
Similar Species: Northern bog violet (Viola nephrophylla) has petals with hairs ("beard") at the base and leaf blades that are almost as long as wide.
Habitat: Occurs in wet soils and among rocks in hanging gardens and cliff seeps, often in relatively deep shade at 3850-7200 ft (1372-2196 m). Co-occurs with Adiantum capillus-veneris, Dodecatheon pulchellum var. zionense, Aquilegia sp., Jamesia americana var. zionis, Vitis arizonica, and Calamagrostis scopulorum (Fertig 2010).
References: Fertig, W. 2010. Rare plants of Zion National Park. Moenave Botanical Consulting, Kanab, UT. 95 pp. Holmgren, N.H., P.K. Holmgren, and A. Cronquist. 2005. Vol. 2 Part B Subclass Dilleniidae. Intermountain Flora, Vascular Plants of the Intermountain West, U.S.A. New York Botanical Garden, Bronx, NY. 488 pp. Welsh, S.L., N.D. Atwood, S. Goodrich, and L.C. Higgins. 2008. A Utah Flora, 2004-2008 summary monograph, fourth edition, revised. Brigham Young University Press, Provo, UT. 1019 pp.
Author: Walter Fertig, Moenave Botanical Consulting, Kanab, UT. April 2017