Montane, subalpine, alpine.  Woodlands, meadows.  Spring, summer.
Lower Stoner Mesa Trail, May 26, 2004.

These very common, tiny, blue-to-purple, spurred violets are often hidden among grasses and taller plants, especially in Aspen forests of Colorado and Utah and to a lesser extent, New Mexico and Arizona. Leaves and flower stems branch from a main stem above ground (in contrast to V. nephrophylla shown below).  Many Viola species commonly cover large areas with scores of flowering plants.  Some species of Viola is almost always blooming in the Four Corners area during spring and summer.

James Edward Smith (1759-1828) named this species in 1817 from a specimen collected by Archibald Menzies along the west coast of North America in 1787-1788.  The plant has endured several dozen name changes.   "Adunca" is Latin for "hooked" and probably refers to the spur at the back of the flower.

Montane, subalpine, alpine.  Woodlands, meadows.  Spring, summer.
Lizard Head Trail, July 2, 2004.

On 12,000 foot tundra, Viola adunca's characteristic spur is no bigger than a mouse's nose, and the whole plant is a miniaturized work of art. 

Montane, subalpine, alpine.  Woodlands, meadows.  Spring, summer.
Navajo Lake Trail, June 25, 2005.

Montane.  Wet meadows and wet open woods.  Spring, summer.
North of Durango, May 29, 2007.

William Weber indicates that Viola nephrophylla is a synonym for Viola sororia but Kartesz and the USDA Plants Database indicate that the two are distinct species: V. sororia  is a central and eastern U.S. species and does not occur in Colorado except perhaps as an escaped cultivated plant (as is the case in central Utah); V. nephrophylla is a western and central U.S. species which does occur in Colorado.  V. sororia has hairy stems and leaf undersides; the photographs show the hairless stems and leaves of V. nephrophylla.

Edward Greene named V. nephrophylla in 1896 from specimens he collected in the Montrose, Colorado area in 1896.  "Nephrophylla" is Greek for "kidney shaped leaves".

Montane.  Wet meadows and wet open woods.  Spring, summer.
North of Durango, May 29, 2007.

Viola nephrophylla enjoys moist roots in wet meadows and other boggy areas.  This characteristic sets it apart from the more common Four Corners blue Violet, V. adunca (above).  V. nephrophylla is also quickly distinguished from V. adunca because it is stemless, i.e., flowers and leaves arise directly from the caudex (the top of the underground root).  Note also the short nub at the back of the flower in contrast to the full spur on V. adunca.