Sharkstooth Trail, June 30, 2000. This is a most common mountain flower and the most common of all Arnicas in our area. It thrives in the dry, acid soils under Spruce and as one enters the dark forest shade from sunny meadows, the bright lemon-yellow Arnica flowers are like beams of lights. It is common to see dozens of single-flowered Arnica plants in one patch with many more carpeting the ground with leafy, flowerless plants. Lizard Head Trail, August 7, 2000.
Arnica prefers subalpine and alpine rocky areas.
Notice the slight serrations in some of the leaves. The species name honors Per Axel Rydberg, a giant in Colorado botany. He wrote Flora of the Rocky Mountains and Adjacent Plains in 1917.