The white flowers of Dryas octopetala are a familiar sight in northern tundra and alpine areas and plenty of mats, some quite large, of it, were to be seen on Horseshoe. An interesting fact about this plant is that it apparently is one of the plants that survived on often isolated mountaintops when the glaciers spread during the ice ages in the valleys below, despite what must have been fierce winter cold. Two primula species exist in the area, the smaller P. angustifolia and the larger P. parryi. Yet another northern genus that left a few representitives behind in North America when it was separated by tectonic activity and rising seas from Eurasia. I was suprised to see Claytonia megarhiza in often wet areas, it looked best where there was plenty of water near it. Some of these huge plants must be many decades old. Lychnis apetala (or Silene uralensis) is a circumpolar species which we found near the top of the mountain. Its calyx is conspicously striped and inflated, the petals barely noticable. Papaver kluanense was rather scarce and only found near the top of the trail. The striking blue Mertensia is M. lanceolata. It is one of the larger plants in the upper part of the trail, with piercing blue flowers. What looks like a refined sweet alyssum is Thlapsi montanum, sometimes called mountain candytuft with good reason. Rhodiola (formerly Sedum) integrifolia does best in moist areas, and is widespread in the Colorado mountains. Particularly nice red ones were seen on Horseshoe, though I saw some paler pink ones on Mt Evans later on. The prize of the hike, the focus of our search efforts, was the tiny blue Eritrichum nanum, a very diminuitive forget me not. It has tiny fuzzy leaves and sky blue flowers. I was especially proud to be the first in our very talented group to find it, even though I had only seen it in photographs before. There may have been more of them in bloom earlier, we found several that were past flowering, not an easy task as they are even more inconspicuous without flowers. This species only grows in the most desolate coldest upper reaches of the mountains in dry rocky areas. There are many white flowered mat forming plants in these alpine reaches, and Arenaria is well represented. This one might be A. obtusiloba. The last pic shows Ranunculus eschscholtzii, another pretty alpine buttercup with rather large flowers.
I'm a high school biology teacher with a passionate interest in plants for as long as I can remember. I have two horticulture degrees, BS and Ph.D. from Cornell and I've worked at the New York Botanical Garden in the past. My plant interests are quite simple: everything! Still, I have a special affection for South African plants, including, of course, pelargoniums (aka "geraniums").