Viola adunca (Blue Violet)

From https://www.swcoloradowildflowers.com/Blue%20Purple%20Enlarged%20Photo%20Pages/viola.htm: Viola adunca variety adunca (Blue Violet)
Violaceae (Violet Family)

Montane, subalpine, alpine.  Woodlands, meadows.  Spring, summer.
Above: Wetland near Little Bear Trail, June 17, 2020 and June 26, 2015; Lower Calico Trail June 11, 2011.
Left: 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, and Viola adunca is no exception, as the photograph at the top of the page indicates. In 2015, late spring snows and rains turned meadows and woodlands blue with tens of thousands of large bouquets of Viola adunca.

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 refers to the spur at the back of the flower.