Viola frank-smithii

An herbaceous plant of the Violet family, distinguished by the following characteristics: (1) perennial, clustered habit; (2) herbage quite glabrous; (3) leaves simple with bases cordate or sometimes truncate; (4) flowers pale violet in color; (5) habitat in cracks and crevices of cliffs and near-vertical outcrops of are carbonate rock; and (6) chromosome number n = 12. The lowermost petal is prolonged backward into a prominent spur that is rounded (not narrowed or upturned) and greenish to pale lime-green in color. Older plants often exhibit a skirt-like mass of dead leaves dangling beneath.

Closely allied to V. adunca, but differs in having the petal spur 1.6 - 2.3 mm long (vs. 3.5 - 7 mm long) and not narrowed or upturned (Utah Native Plant Society 2008). Differs from V. adunca as follows: lime-colored petal spur 1.6-2.3 mm long (vs. 3.5-7 mm long) not narrowed or upturned; white flowers, all purplish dorsally lower 3 with red-violet guidelines vs. normally blue to pale violet, the lower 3 white at base with purple guidelines; leaves broadly obcordate vs. ovate-cordate rounded at base; short stems (6.5 cm) not elongating nor becoming prostrate.

One of the few rock-dwelling violets known in North America. It occurs on cracks and crevices in limestone and dolomite cliffs, mostly on cool, northerly exposures where the plants are often shaded by stands of Douglas-fir. 1645-2070 m elevation.

Endemic to cliffs and near-vertical outcrops of carbonate rock in Logan Canyon and its tributaries. Most of the known locations are on cool, northerly exposures which remain shaded for at least part of the day. Open to dense stands of Douglas-fir (Pseudotsuga menziesii) are usually present on the adjoining canyon slopes, often with Rocky Mountain maple (Acer glabrum) or bigtooth maple (A. grandidentatum) in the understory. This forest cover provides additional shading to the cliff bases where Frank Smith's violet seems to occur in greatest abundance. Within the confines of its rock outcrop habitat, other vascular plant species most commonly associated with Viola frank-smithii are (in decreasing order of frequency): Heuchera rubescens, Petrophyton caespitosum, Musineon lineare, Aster kingii var. kingii, Primula maguirei, Erigeron cronquistii, Cercocarpus ledifolius, Leptodactylon watsonii, Mertensia oblongifolia. Mosses are another frequent associate. It is not uncommon to find the violet on dry but cool and well-shaded cliff faces, the roots often tightly wedged into small cracks and crevices seemingly devoid of any soil material.